diff --git a/src/QueryPath/CSS/EventHandler.php b/src/QueryPath/CSS/EventHandler.php
index a003a0a7..fec92d04 100644
--- a/src/QueryPath/CSS/EventHandler.php
+++ b/src/QueryPath/CSS/EventHandler.php
@@ -19,12 +19,12 @@
  *
  *
  * Typically the parser is not accessed directly. Most developers will use it indirectly from
- * qp(), htmlqp(), or one of the methods on a QueryPath object.
+ * qp3(), htmlqp3(), or one of the methods on a QueryPath object.
  *
  * This parser is modular and is not tied to QueryPath, so you can use it in your
  * own (non-QueryPath) projects if you wish. To dive in, start with EventHandler, the
  * event interface that works like a SAX API for CSS selectors. If you want to check out
- * the details, check out the parser (QueryPath::CSS::Parser),  scanner 
+ * the details, check out the parser (QueryPath::CSS::Parser),  scanner
  * (QueryPath::CSS::Scanner), and token list (QueryPath::CSS::Token).
  */
 
diff --git a/src/QueryPath/DOMQuery.php b/src/QueryPath/DOMQuery.php
index e9dd51be..96ed6438 100644
--- a/src/QueryPath/DOMQuery.php
+++ b/src/QueryPath/DOMQuery.php
@@ -7,20 +7,19 @@
  * was done for a few reasons:
  * - The library has been refactored, and it made more sense to call the top
  *   level class QueryPath. This is not the top level class.
- * - There have been requests for a JSONQuery class, which would be the 
+ * - There have been requests for a JSONQuery class, which would be the
  *   natural complement of DOMQuery.
  */
 
 namespace QueryPath;
 
 use \QueryPath\CSS\QueryPathEventHandler;
-use \QueryPath;
 
 
 /**
  * The DOMQuery object is the primary tool in this library.
  *
- * To create a new DOMQuery, use QueryPath::with() or qp() function.
+ * To create a new DOMQuery, use QueryPath::with() or qp3() function.
  *
  * If you are new to these documents, start at the QueryPath.php page.
  * There you will find a quick guide to the tools contained in this project.
@@ -30,7 +29,7 @@
  * extensions, and there is no guarantee that extensions can serialize. The
  * moral of the story: Don't serialize DOMQuery.
  *
- * @see qp()
+ * @see qp3()
  * @see QueryPath.php
  * @ingroup querypath_core
  */
@@ -85,7 +84,7 @@ class DOMQuery implements \QueryPath\Query, \IteratorAggregate, \Countable {
    * Constructor.
    *
    * Typically, a new DOMQuery is created by QueryPath::with(), QueryPath::withHTML(),
-   * qp(), or htmlqp().
+   * qp3(), or htmlqp3().
    *
    * @param mixed $document
    *   A document-like object.
@@ -93,7 +92,7 @@ class DOMQuery implements \QueryPath\Query, \IteratorAggregate, \Countable {
    *   A CSS 3 Selector
    * @param array $options
    *   An associative array of options.
-   * @see qp()
+   * @see qp3()
    */
   public function __construct($document = NULL, $string = NULL, $options = array()) {
     $string = trim($string);
@@ -203,14 +202,14 @@ public function __construct($document = NULL, $string = NULL, $options = array()
    *
    * This returns an associative array of all of the options as set
    * for the current DOMQuery object. This includes default options,
-   * options directly passed in via {@link qp()} or the constructor,
+   * options directly passed in via {@link qp3()} or the constructor,
    * an options set in the QueryPath::Options object.
    *
    * The order of merging options is this:
-   *  - Options passed in using qp() are highest priority, and will
+   *  - Options passed in using qp3() are highest priority, and will
    *    override other options.
    *  - Options set with QueryPath::Options will override default options,
-   *    but can be overridden by options passed into qp().
+   *    but can be overridden by options passed into qp3().
    *  - Default options will be used when no overrides are present.
    *
    * This function will return the options currently used, with the above option
@@ -219,7 +218,7 @@ public function __construct($document = NULL, $string = NULL, $options = array()
    * @return array
    *  An associative array of options, calculated from defaults and overridden
    *  options.
-   * @see qp()
+   * @see qp3()
    * @see QueryPath::Options::set()
    * @see QueryPath::Options::merge()
    * @since 2.0
@@ -234,7 +233,7 @@ public function getOptions() {
    * This sets the current match to the document's root element. For
    * practical purposes, this is the same as:
    * @code
-   * qp($someDoc)->find(':root');
+   * qp3($someDoc)->find(':root');
    * @endcode
    * However, since it doesn't invoke a parser, it has less overhead. It also
    * works in cases where the QueryPath has been reduced to zero elements (a
@@ -352,7 +351,7 @@ public function size() {
    *
    * @code
    * <?php
-   *  count(qp($xml, 'div'));
+   *  count(qp3($xml, 'div'));
    * ?>
    * @endcode
    *
@@ -377,8 +376,8 @@ public function count() {
    * Calling this method does not change the DOMQuery (e.g. it is
    * non-destructive).
    *
-   * You can use qp()->get() to iterate over all elements matched. You can
-   * also iterate over qp() itself (DOMQuery implementations must be Traversable).
+   * You can use qp3()->get() to iterate over all elements matched. You can
+   * also iterate over qp3() itself (DOMQuery implementations must be Traversable).
    * In the later case, though, each item
    * will be wrapped in a DOMQuery object. To learn more about iterating
    * in QueryPath, see {@link examples/techniques.php}.
@@ -535,7 +534,7 @@ public function hasAttr($attrName) {
    * For example, consider this code:
    * @code
    * <?php
-   * qp(HTML_STUB, 'body')->css('background-color','red')->html();
+   * qp3(HTML_STUB, 'body')->css('background-color','red')->html();
    * ?>
    * @endcode
    * This will return the following HTML:
@@ -547,7 +546,7 @@ public function hasAttr($attrName) {
    * element will be returned unparsed. Example:
    * @code
    * <?php
-   * qp(HTML_STUB, 'body')->css('background-color','red')->css();
+   * qp3(HTML_STUB, 'body')->css('background-color','red')->css();
    * ?>
    * @endcode
    * This will return the following:
@@ -669,7 +668,7 @@ public function dataURL($attr, $data = NULL, $mime = 'application/octet-stream',
       }
     }
     else {
-      $attVal = \QueryPath::encodeDataURL($data, $mime, $context);
+      $attVal = \QueryPath\QueryPath::encodeDataURL($data, $mime, $context);
       return $this->attr($attr, $attVal);
     }
   }
@@ -835,8 +834,8 @@ public function filter($selector) {
    * @code
    * <?php
    * $comp = function (\DOMNode $a, \DOMNode $b) {
-   *   $qpa = qp($a);
-   *   $qpb = qp($b);
+   *   $qpa = qp3($a);
+   *   $qpb = qp3($b);
    *
    *   if ($qpa->text() == $qpb->text()) {
    *     return 0;
@@ -904,7 +903,7 @@ public function sort($comparator, $modifyDOM = FALSE) {
    *
    * Example:
    * @code
-   * qp('li')->filterLambda('qp($item)->attr("id") == "test"');
+   * qp3('li')->filterLambda('qp3($item)->attr("id") == "test"');
    * @endcode
    *
    * The above would filter down the list to only an item whose ID is
@@ -946,11 +945,11 @@ public function filterLambda($fn) {
    * @code
    *  <?php
    *    // This will be 1.
-   *    qp($xml, 'div')->filterPreg('/World/')->size();
+   *    qp3($xml, 'div')->filterPreg('/World/')->size();
    *  ?>
    * @endcode
    *
-   * The return value above will be 1 because the text content of @codeqp($xml, 'div')@endcode is
+   * The return value above will be 1 because the text content of @codeqp3($xml, 'div')@endcode is
    * @codeHello World@endcode.
    *
    * Compare this to the behavior of the <em>:contains()</em> CSS3 pseudo-class.
@@ -1356,7 +1355,7 @@ public function prependTo(DOMQuery $dest) {
    *
    * @param mixed $data
    *  The data to be inserted. This can be XML in a string, a DomFragment, a DOMElement,
-   *  or the other usual suspects. (See {@link qp()}).
+   *  or the other usual suspects. (See {@link qp3()}).
    * @retval object DOMQuery
    *  Returns the DOMQuery with the new modifications. The list of elements currently
    *  selected will remain the same.
@@ -1481,7 +1480,7 @@ public function replaceWith($new) {
    *
    * Now we can run this code:
    * @code
-   *   qp($xml, 'content')->unwrap();
+   *   qp3($xml, 'content')->unwrap();
    * @endcode
    *
    * This will result in:
@@ -1887,7 +1886,7 @@ public function replaceAll($selector, \DOMDocument $document) {
       $node = $document->importNode($node);
       $item->parentNode->replaceChild($node, $item);
     }
-    return QueryPath::with($document, NULL, $this->options);
+    return \QueryPath\QueryPath::with($document, NULL, $this->options);
   }
   /**
    * Add more elements to the current set of matches.
@@ -1910,7 +1909,7 @@ public function add($selector) {
     // This is destructive, so we need to set $last:
     $this->last = $this->matches;
 
-    foreach (QueryPath::with($this->document, $selector, $this->options)->get() as $item) {
+    foreach (\QueryPath\QueryPath::with($this->document, $selector, $this->options)->get() as $item) {
       $this->matches->attach($item);
     }
     return $this;
@@ -1934,12 +1933,12 @@ public function add($selector) {
    * an empty set of matches. Example:
    *
    * @code
-   * // The line below returns the same thing as qp(document, 'p');
-   * qp(document, 'p')->find('div')->end();
+   * // The line below returns the same thing as qp3(document, 'p');
+   * qp3(document, 'p')->find('div')->end();
    * // This returns an empty array:
-   * qp(document, 'p')->end();
+   * qp3(document, 'p')->end();
    * // This returns an empty array:
-   * qp(document, 'p')->find('div')->find('span')->end()->end();
+   * qp3(document, 'p')->find('div')->find('span')->end()->end();
    * @endcode
    *
    * The last one returns an empty array because only one level of changes is stored.
@@ -1964,7 +1963,7 @@ public function end() {
    * Example:
    *
    * @code
-   * qp(document, 'p')->find('div')->andSelf();
+   * qp3(document, 'p')->find('div')->andSelf();
    * @endcode
    *
    * The code above will contain a list of all p elements and all div elements that
@@ -2137,14 +2136,14 @@ public function closest($selector) {
     $found = new \SplObjectStorage();
     foreach ($this->matches as $m) {
 
-      if (QueryPath::with($m, NULL, $this->options)->is($selector) > 0) {
+      if (\QueryPath\QueryPath::with($m, NULL, $this->options)->is($selector) > 0) {
         $found->attach($m);
       }
       else {
         while ($m->parentNode->nodeType !== XML_DOCUMENT_NODE) {
           $m = $m->parentNode;
           // Is there any case where parent node is not an element?
-          if ($m->nodeType === XML_ELEMENT_NODE && QueryPath::with($m, NULL, $this->options)->is($selector) > 0) {
+          if ($m->nodeType === XML_ELEMENT_NODE && \QueryPath\QueryPath::with($m, NULL, $this->options)->is($selector) > 0) {
             $found->attach($m);
             break;
           }
@@ -2179,7 +2178,7 @@ public function parent($selector = NULL) {
         // Is there any case where parent node is not an element?
         if ($m->nodeType === XML_ELEMENT_NODE) {
           if (!empty($selector)) {
-            if (QueryPath::with($m, NULL, $this->options)->is($selector) > 0) {
+            if (\QueryPath\QueryPath::with($m, NULL, $this->options)->is($selector) > 0) {
               $found->attach($m);
               break;
             }
@@ -2214,7 +2213,7 @@ public function parents($selector = NULL) {
         // Is there any case where parent node is not an element?
         if ($m->nodeType === XML_ELEMENT_NODE) {
           if (!empty($selector)) {
-            if (QueryPath::with($m, NULL, $this->options)->is($selector) > 0)
+            if (\QueryPath\QueryPath::with($m, NULL, $this->options)->is($selector) > 0)
               $found->attach($m);
           }
           else
@@ -2305,7 +2304,7 @@ public function html($markup = NULL) {
    * We can retrieve just the contents of this code by doing something like
    * this:
    * @code
-   * qp($xml, 'div')->innerHTML();
+   * qp3($xml, 'div')->innerHTML();
    * @endcode
    *
    * This would return the following:
@@ -2482,10 +2481,10 @@ public function text($text = NULL) {
    * $xml = '<?xml version="1.0"?><root>Foo<a>Bar</a><b/></root>';
    *
    * // This will return 'Foo'
-   * qp($xml, 'a')->textBefore();
+   * qp3($xml, 'a')->textBefore();
    *
    * // This will insert 'Baz' right before <b/>.
-   * qp($xml, 'b')->textBefore('Baz');
+   * qp3($xml, 'b')->textBefore('Baz');
    * ?>
    * @endcode
    *
@@ -2815,7 +2814,7 @@ public function next($selector = NULL) {
         $m = $m->nextSibling;
         if ($m->nodeType === XML_ELEMENT_NODE) {
           if (!empty($selector)) {
-            if (QueryPath::with($m, NULL, $this->options)->is($selector) > 0) {
+            if (\QueryPath\QueryPath::with($m, NULL, $this->options)->is($selector) > 0) {
               $found->attach($m);
               break;
             }
@@ -2852,7 +2851,7 @@ public function nextAll($selector = NULL) {
         $m = $m->nextSibling;
         if ($m->nodeType === XML_ELEMENT_NODE) {
           if (!empty($selector)) {
-            if (QueryPath::with($m, NULL, $this->options)->is($selector) > 0) {
+            if (\QueryPath\QueryPath::with($m, NULL, $this->options)->is($selector) > 0) {
               $found->attach($m);
             }
           }
@@ -2888,7 +2887,7 @@ public function prev($selector = NULL) {
         $m = $m->previousSibling;
         if ($m->nodeType === XML_ELEMENT_NODE) {
           if (!empty($selector)) {
-            if (QueryPath::with($m, NULL, $this->options)->is($selector)) {
+            if (\QueryPath\QueryPath::with($m, NULL, $this->options)->is($selector)) {
               $found->attach($m);
               break;
             }
@@ -2925,7 +2924,7 @@ public function prevAll($selector = NULL) {
         $m = $m->previousSibling;
         if ($m->nodeType === XML_ELEMENT_NODE) {
           if (!empty($selector)) {
-            if (QueryPath::with($m, NULL, $this->options)->is($selector)) {
+            if (\QueryPath\QueryPath::with($m, NULL, $this->options)->is($selector)) {
               $found->attach($m);
             }
           }
@@ -2980,7 +2979,7 @@ public function addClass($class) {
    *
    * Executing this fragment of code will remove only the 'first' class:
    * @code
-   * qp(document, 'element')->removeClass('first');
+   * qp3(document, 'element')->removeClass('first');
    * @endcode
    *
    * The resulting XML will be:
@@ -3069,10 +3068,10 @@ public function hasClass($class) {
    *
    * @code
    * <?php
-   * $qp = qp( QueryPath::HTML_STUB);
-   * $branch = $qp->branch();
+   * $qp = qp3( QueryPath::HTML_STUB);
+   * $branch = $qp3->branch();
    * $branch->find('title')->text('Title');
-   * $qp->find('body')->text('This is the body')->writeHTML;
+   * $qp3->find('body')->text('This is the body')->writeHTML;
    * ?>
    * @endcode
    *
@@ -3111,7 +3110,7 @@ public function hasClass($class) {
    * @see find()
    */
   public function branch($selector = NULL) {
-    $temp = \QueryPath::with($this->matches, NULL, $this->options);
+    $temp = \QueryPath\QueryPath::with($this->matches, NULL, $this->options);
     //if (isset($selector)) $temp->find($selector);
     $temp->document = $this->document;
     if (isset($selector)) $temp->findInPlace($selector);
@@ -3119,7 +3118,7 @@ public function branch($selector = NULL) {
   }
   protected function inst($matches, $selector, $options) {
     /*
-    $temp = \QueryPath::with($matches, NULL, $options);
+    $temp = \QueryPath\QueryPath::with($matches, NULL, $options);
     //if (isset($selector)) $temp->find($selector);
     $temp->document = $this->document;
     if (isset($selector)) $temp->findInPlace($selector);
@@ -3146,7 +3145,7 @@ protected function inst($matches, $selector, $options) {
    *
    * This is a destructive operation, which means that end() will revert
    * the list back to the clone's original.
-   * @see qp()
+   * @see qp3()
    * @retval object DOMQuery
    */
   public function cloneAll() {
@@ -3479,7 +3478,7 @@ public function nextUntil($selector = NULL) {
         $m = $m->nextSibling;
         if ($m->nodeType === XML_ELEMENT_NODE) {
           if (!empty($selector)) {
-            if (QueryPath::with($m, NULL, $this->options)->is($selector) > 0) {
+            if (\QueryPath\QueryPath::with($m, NULL, $this->options)->is($selector) > 0) {
               break;
             }
             else {
@@ -3520,7 +3519,7 @@ public function prevUntil($selector = NULL) {
       while (isset($m->previousSibling)) {
         $m = $m->previousSibling;
         if ($m->nodeType === XML_ELEMENT_NODE) {
-          if (!empty($selector) && QueryPath::with($m, NULL, $this->options)->is($selector))
+          if (!empty($selector) && \QueryPath\QueryPath::with($m, NULL, $this->options)->is($selector))
           break;
           else
           $found->attach($m);
@@ -3553,7 +3552,7 @@ public function parentsUntil($selector = NULL) {
         // Is there any case where parent node is not an element?
         if ($m->nodeType === XML_ELEMENT_NODE) {
           if (!empty($selector)) {
-            if (QueryPath::with($m, NULL, $this->options)->is($selector) > 0)
+            if (\QueryPath\QueryPath::with($m, NULL, $this->options)->is($selector) > 0)
             break;
             else
             $found->attach($m);
@@ -3683,7 +3682,7 @@ public function setMatches($matches, $unique = TRUE) {
       $this->matches = $found;
     }
 
-    // EXPERIMENTAL: Support for qp()->length.
+    // EXPERIMENTAL: Support for qp3()->length.
     $this->length = $this->matches->count();
   }
 
@@ -3829,7 +3828,7 @@ public function __call($name, $arguments) {
     // enough extensions.)
     //
     // The main reason for moving this out of the constructor is that most
-    // new DOMQuery instances do not use extensions. Charging qp() calls
+    // new DOMQuery instances do not use extensions. Charging qp3() calls
     // with the additional hit is not a good idea.
     //
     // Also, this will at least limit the number of circular references.
diff --git a/src/QueryPath/Extension.php b/src/QueryPath/Extension.php
index ec370ca7..eeefb438 100644
--- a/src/QueryPath/Extension.php
+++ b/src/QueryPath/Extension.php
@@ -75,13 +75,13 @@
  * QueryPath extensions are called like regular QueryPath functions. For
  * example, the extension above can be called like this:
  * <code>
- * qp('some.xml')->stubToe();
+ * qp3('some.xml')->stubToe();
  * // or
  * QueryPath::with('some.xml')->stubToe();
  * </code>
  * Since it returns the Query ($qp) object, chaining is supported:
  * <code>
- * print qp('some.xml')->stubToe()->xml();
+ * print qp3('some.xml')->stubToe()->xml();
  * </code>
  * When you write your own extensions, anything that does not need to return a
  * specific value should return the Query object. Between that and the
diff --git a/src/QueryPath/Extension/QPXML.php b/src/QueryPath/Extension/QPXML.php
index fc3470e9..11c9ad99 100644
--- a/src/QueryPath/Extension/QPXML.php
+++ b/src/QueryPath/Extension/QPXML.php
@@ -187,7 +187,7 @@ public function createElement($text, $nsUri = null) {
       } else {
         $node = $element->ownerDocument->createElement($text);
       }
-        return QueryPath::with($node);
+        return \QueryPath\QueryPath::with($node);
       }
     }
     return;
@@ -203,7 +203,7 @@ public function appendElement($text) {
     if (isset ($text)) {
       foreach ($this->qp->get() as $element) {
         $node = $this->qp->createElement($text);
-        QueryPath::with($element)->append($node);
+        \QueryPath\QueryPath::with($element)->append($node);
       }
     }
     return $this->qp;
diff --git a/src/QueryPath/Extension/QPXSL.php b/src/QueryPath/Extension/QPXSL.php
index 6a2727c6..40ea7b0a 100644
--- a/src/QueryPath/Extension/QPXSL.php
+++ b/src/QueryPath/Extension/QPXSL.php
@@ -30,7 +30,7 @@
  * require 'QueryPath/QueryPath.php';
  * require 'QueryPath/Extension/QPXSL.php';
  *
- * qp('src.xml')->xslt('stylesheet.xml')->writeXML();
+ * qp3('src.xml')->xslt('stylesheet.xml')->writeXML();
  * ?>
  *
  * This will transform src.xml according to the XSLT rules in
@@ -56,7 +56,7 @@ public function __construct(\QueryPath\Query $qp) {
    *
    * @param mixed $style
    *  This takes a QueryPath object or <em>any</em> of the types that the
-   *  {@link qp()} function can take.
+   *  {@link qp3()} function can take.
    * @return QueryPath
    *  A QueryPath object wrapping the transformed document. Note that this is a
    *  <i>different</em> document than the original. As such, it has no history.
@@ -64,13 +64,13 @@ public function __construct(\QueryPath\Query $qp) {
    *  the original source document will remain unchanged.)
    */
   public function xslt($style) {
-    if (!($style instanceof QueryPath)) {
-      $style = \QueryPath::with($style);
+    if (!($style instanceof \QueryPath\QueryPath)) {
+      $style = \QueryPath\QueryPath::with($style);
     }
     $sourceDoc = $this->src->top()->get(0)->ownerDocument;
     $styleDoc = $style->get(0)->ownerDocument;
     $processor = new \XSLTProcessor();
     $processor->importStylesheet($styleDoc);
-    return \QueryPath::with($processor->transformToDoc($sourceDoc));
+    return \QueryPath\QueryPath::with($processor->transformToDoc($sourceDoc));
   }
 }
diff --git a/src/QueryPath/ExtensionRegistry.php b/src/QueryPath/ExtensionRegistry.php
index 963edd3e..a16b7a97 100644
--- a/src/QueryPath/ExtensionRegistry.php
+++ b/src/QueryPath/ExtensionRegistry.php
@@ -122,7 +122,7 @@ public static function extensionNames() {
    *
    * If extension autoloading is disabled, then QueryPath will not
    * automatically load all registred extensions when a new Query
-   * object is created using qp().
+   * object is created using qp3().
    */
   public static function autoloadExtensions($boolean = TRUE) {
     self::$useRegistry = $boolean;
diff --git a/src/QueryPath/Options.php b/src/QueryPath/Options.php
index 846984db..7fa53440 100644
--- a/src/QueryPath/Options.php
+++ b/src/QueryPath/Options.php
@@ -20,11 +20,11 @@
  * When a QueryPath object is created, it will evaluate options in the
  * following order:
  *
- * - Options passed into qp() have highest priority.
+ * - Options passed into qp3() have highest priority.
  * - Options in QueryPath::Options (this class) have the next highest priority.
  * - If the option is not specified elsewhere, QueryPath will use its own defaults.
  *
- * @see qp()
+ * @see qp3()
  * @see QueryPath::Options::set()
  * @ingroup querypath_util
  */
diff --git a/src/QueryPath.php b/src/QueryPath/QueryPath.php
similarity index 96%
rename from src/QueryPath.php
rename to src/QueryPath/QueryPath.php
index 55601d5f..cc5c27a5 100644
--- a/src/QueryPath.php
+++ b/src/QueryPath/QueryPath.php
@@ -7,7 +7,7 @@
  * build, parse, search, and modify DOM documents.
  *
  * To use QueryPath, only one file must be imported: qp.php. This file defines
- * the `qp()` function, and also registers an autoloader if necessary.
+ * the `qp3()` function, and also registers an autoloader if necessary.
  *
  * Standard usage:
  * @code
@@ -17,7 +17,7 @@
  * $xml = '<?xml version="1.0"?><test><foo id="myID"/></test>';
  *
  * // Procedural call a la jQuery:
- * $qp = qp($xml, '#myID');
+ * $qp = qp3($xml, '#myID');
  * $qp->append('<new><elements/></new>')->writeHTML();
  *
  * // Object-oriented version with a factory:
@@ -43,7 +43,7 @@
  * To gain familiarity with QueryPath, the following three API docs are
  * the best to start with:
  *
- *- qp(): This function constructs new queries, and is the starting point
+ *- qp3(): This function constructs new queries, and is the starting point
  *  for manipulating a document. htmlqp() is an alias tuned for HTML
  *  documents (especially old HTML), and QueryPath::with(), QueryPath::withXML()
  *  and QueryPath::withHTML() all perform a similar role, but in a purely
@@ -75,7 +75,7 @@
  * @author M Butcher <matt @aleph-null.tv>
  * @license MIT
  * @see QueryPath
- * @see qp()
+ * @see qp3()
  * @see http://querypath.org The QueryPath home page.
  * @see http://api.querypath.org An online version of the API docs.
  * @see http://technosophos.com For how-tos and examples.
@@ -84,6 +84,8 @@
  *
  */
 
+namespace QueryPath;
+
 /**
  *
  */
@@ -142,11 +144,11 @@ class QueryPath {
    * fragment. For example, you should use {@link xml()}, {@link innerXML()}, and
    * {@link writeXML()}.
    *
-   * This can be passed into {@link qp()} to begin a new basic HTML document.
+   * This can be passed into {@link qp3()} to begin a new basic HTML document.
    *
    * Example:
    * @code
-   * $qp = qp(QueryPath::XHTML_STUB); // Creates a new XHTML document
+   * $qp = qp3(QueryPath::XHTML_STUB); // Creates a new XHTML document
    * $qp->writeXML(); // Writes the document as well-formed XHTML.
    * @endcode
    * @since 2.0
@@ -196,7 +198,7 @@ public static function withHTML($source = NULL, $selector = NULL, $options = arr
   /**
    * Enable one or more extensions.
    *
-   * Extensions provide additional features to QueryPath. To enable and 
+   * Extensions provide additional features to QueryPath. To enable and
    * extension, you can use this method.
    *
    * In this example, we enable the QPTPL extension:
diff --git a/src/QueryPath/QueryPathIterator.php b/src/QueryPath/QueryPathIterator.php
index be2e66f0..39c55ce2 100644
--- a/src/QueryPath/QueryPathIterator.php
+++ b/src/QueryPath/QueryPathIterator.php
@@ -21,7 +21,7 @@ class QueryPathIterator extends \IteratorIterator {
 
   public function current() {
     if (!isset($this->qp)) {
-      $this->qp = \QueryPath::with(parent::current(), NULL, $this->options);
+      $this->qp = \QueryPath\QueryPath::with(parent::current(), NULL, $this->options);
     }
     else {
       $splos = new \SplObjectStorage();
diff --git a/src/documentation.php b/src/documentation.php
index 3649a5b6..3c5216c7 100644
--- a/src/documentation.php
+++ b/src/documentation.php
@@ -6,21 +6,21 @@
  *
  * @section getting_started Getting Started
  *
- * To being using QueryPath, you will probably want to take a look at these three pieces of 
+ * To being using QueryPath, you will probably want to take a look at these three pieces of
  * documentation:
- *  - qp(): The main QueryPath function (like jQuery's $ function.)
- *  - htmlqp(): A specialized version of qp() for dealing with poorly formatted HTML.
+ *  - qp3(): The main QueryPath function (like jQuery's $ function.)
+ *  - htmlqp3(): A specialized version of qp3() for dealing with poorly formatted HTML.
  *  - QueryPath: The QueryPath class, which has all of the main functions.
  *
- * One substantial difference from jQuery is that QueryPath does not return a new object for 
+ * One substantial difference from jQuery is that QueryPath does not return a new object for
  * each call (for performance reasons). Instead, the same object is mutated from call to call.
  * A chain, then, typically performs all methods on the same object.
- * When you need multiple objects, QueryPath has a {@link QueryPath::branch()} function that 
+ * When you need multiple objects, QueryPath has a {@link QueryPath::branch()} function that
  * will return a cloned QueryPath object.
  *
- * QueryPath also has numerous functions that jQuery does not. Some (like QueryPath::top() and 
+ * QueryPath also has numerous functions that jQuery does not. Some (like QueryPath::top() and
  * QueryPath::dataURL()) are extensions we find useful.
- * Most, however, are to either emphasize PHP features (QueryPath::filterPreg()) or adapt to 
+ * Most, however, are to either emphasize PHP features (QueryPath::filterPreg()) or adapt to
  * server-side needs (QueryPathEntities::replaceAllEntities()).
  *
  * @subsection basic_example A Few Basic Examples
@@ -29,57 +29,57 @@
  *
  * @code
  * require 'QueryPath/QueryPath.php';
- * 
- * qp('<?xml version="1.0"?><root><foo/></root>', 'foo')->append('<bar>baz</bar>')->writeXML();
+ *
+ * qp3('<?xml version="1.0"?><root><foo/></root>', 'foo')->append('<bar>baz</bar>')->writeXML();
  * @endcode
  *
- * The above will create a new document from the XML string, find the <code>foo</code> element, and then 
+ * The above will create a new document from the XML string, find the <code>foo</code> element, and then
  * append the <code>bar</code> element (complete with its text). Finally, the call to QueryPath::writeXML() will
  * print the entire finished XML document to standard out (usually the web browser).
  *
- * Here's an example using htmlqp():
+ * Here's an example using htmlqp3():
  *
  * @code
  * require 'QueryPath/QueryPath.php';
- * 
+ *
  * // URL to fetch:
  * $url = 'http://technosophos.com';
  *
- * print htmlqp($url, 'title')->text();
+ * print htmlqp3($url, 'title')->text();
  * @endcode
  *
  * The above will fetch the HTML from the given URL and then find the <code>title</code> tag. It will extract
  * the text (QueryPath::text()) from the title and print it.
  *
- * For more examples, check out the #Examples namespace (start with {@link examples/html.php}). Also, read about the 
- * qp() and htmlqp() functions.
+ * For more examples, check out the #Examples namespace (start with {@link examples/html.php}). Also, read about the
+ * qp3() and htmlqp3() functions.
  *
  * @subsection online_sources Online Sources
  *
  *   - The official QueryPath site http://querypath.org
  *   - The latest API docs http://api.querypath.org
- *   - IBM DeveloperWorks Intro to QueryPath http://www.ibm.com/developerworks/web/library/os-php-querypath/index.html 
+ *   - IBM DeveloperWorks Intro to QueryPath http://www.ibm.com/developerworks/web/library/os-php-querypath/index.html
  *   - QueryPath articles at TechnoSophos.Com http://technosophos.com/qp/articles
  *   - The QueryPath GitHub repository http://github.com/technosophos/querypath
  *
- * If you find a good online resource, please submit it as an issue in GitHub, and we will 
+ * If you find a good online resource, please submit it as an issue in GitHub, and we will
  * most likely add it here.
  *
  * @subsection more_examples A Larger Example
  *
  * @include examples/html.php
- * 
+ *
  * @page extensions Using and Writing Extensions
  *
  * Using an extension is as easy as including it in your code:
- * 
+ *
  * @code
  * <?php
  * require 'QueryPath/QueryPath.php';
  * require 'QueryPath/Extension/QPXML.php';
  *
  * // Now I have the QPXML methods available:
- * qp(QueryPath::HTML_STUB)->comment('This is an HTML comment.');
+ * qp3(\QueryPath\QueryPath::HTML_STUB)->comment('This is an HTML comment.');
  * ?>
  * @endcode
  *
@@ -91,45 +91,45 @@
  * QueryPathExtension is the master interface for all extensions.
  *
  */
- 
+
 
 /** @page CSSReference CSS Selector Reference
- * QueryPath provides two query 'languages' that you can use to search through XML and HTML 
+ * QueryPath provides two query 'languages' that you can use to search through XML and HTML
  * documents. The main query language is an implementation of the CSS3 Selectors specification. This
  * is the query language that jQuery and CSS use -- and more recently, FireFox itself supports it
  * via its JavaScript API. CSS3 should be familiar to developers and designers who have worked with
  * HTML and stylesheets.
  *
- * QueryPath also allows XPath selectors, which can be executed using QueryPath::xpath(). While 
+ * QueryPath also allows XPath selectors, which can be executed using QueryPath::xpath(). While
  * fewer functions take XPath expressions, it is noless a powerful tool for querying DOM objects.
  *
  * @code
  * <?php
- * qp($xml)->xpath('//foo');
+ * qp3($xml)->xpath('//foo');
  * ?>
  * @endcode
- * 
+ *
  * QueryPath provides a full CSS3 selector implementation, including all of the specified operators,
  * robost not() and has() support, pseudo-class/elements, and XML namespace support.
  *
- * Selectors can be passed into a number of QueryPath functions including qp(), htmlqp(), 
+ * Selectors can be passed into a number of QueryPath functions including qp3(), htmlqp3(),
  * QueryPath::find(), QueryPath::top(), QueryPath::children() and others.
  * @code
  * <?php
- * $qp = qp($html, 'body'); // Find the body
+ * $qp = qp3($html, 'body'); // Find the body
  * $another_qp = $qp->branch('p'); // Create another QP object that searches BODY for P tags.
  * $qp->find('strong>a'); // Find all of the A elements directly inside of STRONG elements.
  * $qp->top('head'); // Start over at the top of the document, and find the HEAD tag.
  * ?>
  * @endcode
  *
- * In all of the examples above, CSS selectors are used to locate specific things inside of the 
+ * In all of the examples above, CSS selectors are used to locate specific things inside of the
  * document.
  *
  * @section selector_examples Example Selectors
  * Example selectors:
  * - <code>p</code>: Select all P elements in a document.
- * - <code>strong a</code>: Select any A elements that are inside (children or descendants of) a STRONG 
+ * - <code>strong a</code>: Select any A elements that are inside (children or descendants of) a STRONG
  *    element.
  * - <code>strong>a</code>: Select only A elements that are directly beneath STRONG elements.
  * - <code>:root>head</code> select HEAD elements that are directly beneath the document root.
@@ -141,15 +141,15 @@
  * - <code>p:not(.nav)</code>: Select any elements in P that do not have the nav class.
  *
  * @section pseudo_reference Pseudo-class and pseudo-element selectors
- * QueryPath provides an implementation of the CSS3 spec, including the CSS3 pseudo-classes and 
+ * QueryPath provides an implementation of the CSS3 spec, including the CSS3 pseudo-classes and
  * pseudo-elements defined in the spec. Some of the CSS3 pseudo-classes require a user agent, and
  * so cannot be adequately captured on the server side, but all others have been implemented.
  *
  * Additionally, jQuery has added its own pseudo-classes, and jQuery users have come to expect those
- * to work. So for the sake of convenience, we have implemented those as well. These include the 
+ * to work. So for the sake of convenience, we have implemented those as well. These include the
  * form pseudo-classes, along with several others.
  *
- * Finally, QueryPath has added a couple of useful pseudo-classes, namely :x-root and 
+ * Finally, QueryPath has added a couple of useful pseudo-classes, namely :x-root and
  * :contains-exactly.
  *
  * @subsection pseudoelement_ref Pseudo-Elements
@@ -170,7 +170,7 @@
  *
  * @code
  * <?php
- * $textNode = qp($xml, 'p::first-letter')->get();
+ * $textNode = qp3($xml, 'p::first-letter')->get();
  * ?>
  * @endcode
  *
@@ -221,7 +221,7 @@
  * - has: Matches any items that have children that match the given selector, e.g. <code>:has(strong>a)</code>
  * - contains: Contains *text* that matches. This is a substring match.
  * - contains-exactly: Contains *exactly* the given text. This is NOT a substring match.
- * 
+ *
  * These generate errors because they are not implemented:
  * - indeterminate
  * - lang
@@ -239,23 +239,23 @@
  * Examples:
  * @code
  * <?php
- * qp($html, 'form input:text'); // Get all text input elements in a form.
+ * qp3($html, 'form input:text'); // Get all text input elements in a form.
  * ?>
  * @endcode
  * @section xml_namespaces XML Namespaces
  * QueryPath also supports the CSS3 namespace selection syntax. <b>This is syntactically different
- * than the XML namespace tag format</b>. To select a tag whose namespaced name is foo:bar, the 
- * CSS element selector would be <code>foo|bar</code> (note the vertical bar instead of a colon). While 
- * QueryPath does its best to resolve namespaces to short names, there is a possibility that a 
+ * than the XML namespace tag format</b>. To select a tag whose namespaced name is foo:bar, the
+ * CSS element selector would be <code>foo|bar</code> (note the vertical bar instead of a colon). While
+ * QueryPath does its best to resolve namespaces to short names, there is a possibility that a
  * malformed namespace will prevent specific namespace queries.
  *
  * You can also query across namespaces with <code>*|tagname</code>.
  *
  * @code
  * <?php
- * qp($xml, 'atom|entry'); // Find all <atom:entry> elements.
- * qp($xml, 'atom|entry > xmedia|video'); // Find all <xmedia:video> elements directly inside <atom:entry> elements.
- * qp($xml, '*|entry'); // Find any namespaced tag that has `entry` as the tag name.
+ * qp3($xml, 'atom|entry'); // Find all <atom:entry> elements.
+ * qp3($xml, 'atom|entry > xmedia|video'); // Find all <xmedia:video> elements directly inside <atom:entry> elements.
+ * qp3($xml, '*|entry'); // Find any namespaced tag that has `entry` as the tag name.
  * ?>
  * @endcode
  */
diff --git a/src/qp.php b/src/qp.php
index 1b9fa2fc..e60a4010 100644
--- a/src/qp.php
+++ b/src/qp.php
@@ -12,13 +12,13 @@
  * <?php
  * require 'qp.php';
  *
- * qp($xml)->find('foo')->count();
+ * qp3($xml)->find('foo')->count();
  * ?>
  * @endcode
  *
  * If no autoloader is currently operating, this will use
- * QueryPath's default autoloader **unless** 
- * QP_NO_AUTOLOADER is defined, in which case all of the 
+ * QueryPath's default autoloader **unless**
+ * QP_NO_AUTOLOADER is defined, in which case all of the
  * files will be statically required in.
  */
 
@@ -55,7 +55,7 @@
     require __DIR__ . '/QueryPath/Options.php';
     require __DIR__ . '/QueryPath/QueryPathIterator.php';
     require __DIR__ . '/QueryPath/DOMQuery.php';
-    require __DIR__ . '/QueryPath.php';
+    require __DIR__ . '/QueryPath/QueryPath.php';
   }
   else {
     spl_autoload_register(function ($klass) {
@@ -70,7 +70,7 @@
   }
 }
 
-// Define qp() and qphtml() function.
-if (!function_exists('qp')) {
+// Define qp3() and qphtml3() function.
+if (!function_exists('qp3')) {
     require __DIR__ . '/qp_functions.php';
 }
\ No newline at end of file
diff --git a/src/qp_functions.php b/src/qp_functions.php
index 2da04818..dab4fdbd 100644
--- a/src/qp_functions.php
+++ b/src/qp_functions.php
@@ -12,7 +12,7 @@
  * <?php
  * require 'qp.php';
  *
- * qp($xml)->find('foo')->count();
+ * qp3($xml)->find('foo')->count();
  * ?>
  * @endcode
  */
@@ -21,7 +21,7 @@
  * Core classes and functions for QueryPath.
  *
  * These are the classes, objects, and functions that developers who use QueryPath
- * are likely to use. The qp() and htmlqp() functions are the best place to start,
+ * are likely to use. The qp3() and htmlqp3() functions are the best place to start,
  * while most of the frequently used methods are part of the QueryPath object.
  */
 
@@ -56,14 +56,14 @@
  * Example:
  * @code
  * <?php
- * qp(); // New empty QueryPath
- * qp('path/to/file.xml'); // From a file
- * qp('<html><head></head><body></body></html>'); // From HTML or XML
- * qp(QueryPath::XHTML_STUB); // From a basic HTML document.
- * qp(QueryPath::XHTML_STUB, 'title'); // Create one from a basic HTML doc and position it at the title element.
+ * qp3(); // New empty QueryPath
+ * qp3('path/to/file.xml'); // From a file
+ * qp3('<html><head></head><body></body></html>'); // From HTML or XML
+ * qp3(\QueryPath\QueryPath::XHTML_STUB); // From a basic HTML document.
+ * qp3(\QueryPath\QueryPath::XHTML_STUB, 'title'); // Create one from a basic HTML doc and position it at the title element.
  *
  * // Most of the time, methods are chained directly off of this call.
- * qp(QueryPath::XHTML_STUB, 'body')->append('<h1>Title</h1>')->addClass('body-class');
+ * qp3(\QueryPath\QueryPath::XHTML_STUB, 'body')->append('<h1>Title</h1>')->addClass('body-class');
  * ?>
  * @endcode
  *
@@ -73,7 +73,7 @@
  *
  * <b>Types of documents that QueryPath can support</b>
  *
- *  qp() can take any of these as its first argument:
+ *  qp3() can take any of these as its first argument:
  *
  *  - A string of XML or HTML (See {@link XHTML_STUB})
  *  - A path on the file system or a URL
@@ -135,7 +135,7 @@
  *    If you want to change this, you can set this option with one of the
  *    JS_CSS_ESCAPE_* constants, or you can write your own.
  *  - QueryPath_class: (ADVANCED) Use this to set the actual classname that
- *    {@link qp()} loads as a QueryPath instance. It is assumed that the
+ *    {@link qp3()} loads as a QueryPath instance. It is assumed that the
  *    class is either {@link QueryPath} or a subclass thereof. See the test
  *    cases for an example.
  *
@@ -148,14 +148,14 @@
  *  An associative array of options. Currently supported options are listed above.
  * @return QueryPath
  */
-function qp($document = NULL, $string = NULL, $options = array()) {
-    return QueryPath::with($document, $string, $options);
+function qp3($document = NULL, $string = NULL, $options = array()) {
+    return \QueryPath\QueryPath::with($document, $string, $options);
 }
 
 /**
- * A special-purpose version of {@link qp()} designed specifically for HTML.
+ * A special-purpose version of {@link qp3()} designed specifically for HTML.
  *
- * XHTML (if valid) can be easily parsed by {@link qp()} with no problems. However,
+ * XHTML (if valid) can be easily parsed by {@link qp3()} with no problems. However,
  * because of the way that libxml handles HTML, there are several common steps that
  * need to be taken to reliably parse non-XML HTML documents. This function is
  * a convenience tool for configuring QueryPath to parse HTML.
@@ -168,14 +168,47 @@ function qp($document = NULL, $string = NULL, $options = array()) {
  *
  * Parser warning messages are also suppressed, so if the parser emits a warning,
  * the application will not be notified. This is equivalent to
- * calling @code@qp()@endcode.
+ * calling @code@qp3()@endcode.
  *
  * Warning: Character set conversions will only work if the Multi-Byte (mb) library
  * is installed and enabled. This is usually enabled, but not always.
  *
  * @ingroup querypath_core
- * @see qp()
+ * @see qp3()
  */
-function htmlqp($document = NULL, $selector = NULL, $options = array()) {
-    return QueryPath::withHTML($document, $selector, $options);
-}
\ No newline at end of file
+function htmlqp3($document = NULL, $selector = NULL, $options = array()) {
+    return \QueryPath\QueryPath::withHTML($document, $selector, $options);
+}
+
+/*
+ * Register the old API in the global namespace for backwards compatibility
+ * except an old querypath version has been loaded already.
+ */
+if (!function_exists('qp')) {
+
+  /**
+   * Backwards compatibility wrapper for qp3().
+   *
+   * @ingroup querypath_core
+   * @see qp3()
+   */
+  function qp($document = NULL, $string = NULL, $options = array()) {
+    return qp3($document, $string, $options);
+  }
+
+  /**
+   * Backwards compatibility wrapper for htmlqp3().
+   *
+   * @ingroup querypath_core
+   * @see htmlqp3()
+   */
+  function htmlqp($document = NULL, $selector = NULL, $options = array()) {
+    return htmlqp3($document, $selector, $options);
+  }
+
+  /**
+   * Populate QueryPath class to global namespace for backwards compatibility.
+   */
+  class_alias('\\QueryPath\\QueryPath', '\\QueryPath');
+
+}