diff --git a/README.md b/README.md
index 4118689..2112e6f 100644
--- a/README.md
+++ b/README.md
@@ -33,9 +33,29 @@ Simple usecase:
 ```python
 >>> import truecase
 >>> truecase.get_true_case('hey, what is the weather in new york?')
-'Hey, what is the weather in New York?''
+'Hey, what is the weather in New York?'
 ```
 
+You can also pass an `out_of_vocabulary_token_option`, which will be used if a word is not found in the model's vocabulary:
+```python
+>>> import truecase
+>>> truecase.get_true_case('my favorite music genre is hip-hop.', "title")
+'My favorite music genre is Hip-Hop.'
+```
+`out_of_vocabulary_token_option`:
+- "title" < DEFAULT
+- "capitalize"
+- "lower"
+- Or, pass if your own lambda function (takes the token with original casing as a single parameter)
+
+*If an invalid option is passed, title is used*
+
+Lambda function example:
+```python
+>>> import truecase
+>>> truecase.get_true_case('i work in the nsa.', lambda token: token.upper())
+'I work in the NSA.'
+```
 ## Training your own model
 
 TODO. For now refer to Trainer.py
diff --git a/tests/test_truecase.py b/tests/test_truecase.py
index d6a5edf..016c511 100644
--- a/tests/test_truecase.py
+++ b/tests/test_truecase.py
@@ -47,3 +47,8 @@ def test_get_true_case(self):
         expected = "Testing $bug"
         result = self.tc.get_true_case(sentence)
         assert result == expected
+
+        sentence = "i work in the nsa."
+        expected = "I work in the NSA."
+        result = self.tc.get_true_case(sentence, lambda token: token.upper())
+        assert result == expected
diff --git a/truecase/TrueCaser.py b/truecase/TrueCaser.py
index 29253fb..fed333d 100644
--- a/truecase/TrueCaser.py
+++ b/truecase/TrueCaser.py
@@ -2,6 +2,7 @@
 import os
 import pickle
 import string
+from typing import Callable
 
 import nltk
 from nltk.tokenize import word_tokenize
@@ -91,6 +92,19 @@ def get_score(self, prev_token, possible_token, next_token):
     def first_token_case(self, raw):
         return raw.capitalize()
 
+    def out_of_vocabulary_handler(self, token_og_case, out_of_vocabulary_token_option="title"):
+        if isinstance(out_of_vocabulary_token_option, Callable):
+            return out_of_vocabulary_token_option(token_og_case)
+        elif out_of_vocabulary_token_option == "title":
+            return token_og_case.title()
+        elif out_of_vocabulary_token_option == "capitalize":
+            return token_og_case.capitalize()
+        elif out_of_vocabulary_token_option == "lower":
+            return token_og_case.lower()
+        else:
+            # If value passed is invalid, use .title()
+            return token_og_case.title()
+
     def get_true_case(self, sentence, out_of_vocabulary_token_option="title"):
         """ Wrapper function for handling untokenized input.
         
@@ -121,7 +135,7 @@ def get_true_case_from_tokens(self, tokens, out_of_vocabulary_token_option="titl
         """
         tokens_true_case = []
         for token_idx, token in enumerate(tokens):
-
+            token_og_case = token
             if token in string.punctuation or token.isdigit():
                 tokens_true_case.append(token)
             else:
@@ -154,14 +168,7 @@ def get_true_case_from_tokens(self, tokens, out_of_vocabulary_token_option="titl
                             tokens_true_case[0])
 
                 else:  # Token out of vocabulary
-                    if out_of_vocabulary_token_option == "title":
-                        tokens_true_case.append(token.title())
-                    elif out_of_vocabulary_token_option == "capitalize":
-                        tokens_true_case.append(token.capitalize())
-                    elif out_of_vocabulary_token_option == "lower":
-                        tokens_true_case.append(token.lower())
-                    else:
-                        tokens_true_case.append(token)
+                    tokens_true_case.append(self.out_of_vocabulary_handler(token_og_case, out_of_vocabulary_token_option))
 
         return tokens_true_case