diff --git a/README.md b/README.md
index c6f7186..ed88b01 100644
--- a/README.md
+++ b/README.md
@@ -31,8 +31,21 @@ Usage
 $builder->add('enabled', BooleanType::class);
 ```
 
-The form type use a data transformer which will transform the value to `true` (`1`, `'1'`, `true` or `'true'`)
-or `false` (`0`, `'0'`, `false` or `'false'`).
+By default, the form type use a data transformer which will transform the value to `true` (`1`, `'1'`, `true` and
+`'true'`) or `false` (`0`, `'0'`, `false` and `'false'`).
+
+If you want to support more values, you can override the `true_values` and `false_values` form type options:
+
+```php
+$builder
+    ->add('enabled', BooleanType::class,
+        array(
+            'true_values' => array(1, '1', true, 'true', 'on', 'yes'),
+            'false_values' => array(0, '0', false, 'false', 'off', 'no'),
+        )
+    )
+;
+```
 
 > **Note:** The form type is not intended to be displayed on a browser: use the built-in `CheckboxType` form type
 > provided by Symfony instead.
diff --git a/src/Form/DataTransformer/BooleanTypeToBooleanTransformer.php b/src/Form/DataTransformer/BooleanTypeToBooleanTransformer.php
index 0d67d4e..02bfa46 100644
--- a/src/Form/DataTransformer/BooleanTypeToBooleanTransformer.php
+++ b/src/Form/DataTransformer/BooleanTypeToBooleanTransformer.php
@@ -2,7 +2,6 @@
 
 namespace FSevestre\BooleanFormType\Form\DataTransformer;
 
-use FSevestre\BooleanFormType\Form\Type\BooleanType;
 use Symfony\Component\Form\DataTransformerInterface;
 use Symfony\Component\Form\Exception\TransformationFailedException;
 
@@ -11,6 +10,15 @@
  */
 final class BooleanTypeToBooleanTransformer implements DataTransformerInterface
 {
+    private $trueValues;
+    private $falseValues;
+
+    public function __construct(array $trueValues, array $falseValues)
+    {
+        $this->trueValues = $trueValues;
+        $this->falseValues = $falseValues;
+    }
+
     public function transform($value)
     {
         if (null === $value) {
@@ -30,9 +38,9 @@ public function reverseTransform($value)
             return false; // `false` and empty values are converted to `null` during form submission.
         }
 
-        if (in_array($value, BooleanType::$TRUE_VALUES, true)) {
+        if (in_array($value, $this->trueValues, true)) {
             return true;
-        } elseif (in_array($value, BooleanType::$FALSE_VALUES, true)) {
+        } elseif (in_array($value, $this->falseValues, true)) {
             return false;
         }
 
diff --git a/src/Form/Type/BooleanType.php b/src/Form/Type/BooleanType.php
index 33f45e9..db40f4d 100644
--- a/src/Form/Type/BooleanType.php
+++ b/src/Form/Type/BooleanType.php
@@ -12,18 +12,17 @@
  */
 final class BooleanType extends AbstractType
 {
-    public static $FALSE_VALUES = array(0, '0', false, 'false');
-    public static $TRUE_VALUES = array(1, '1', true, 'true');
-
     public function buildForm(FormBuilderInterface $builder, array $options)
     {
-        $builder->addModelTransformer(new BooleanTypeToBooleanTransformer());
+        $builder->addModelTransformer(new BooleanTypeToBooleanTransformer($options['true_values'], $options['false_values']));
     }
 
     public function configureOptions(OptionsResolver $resolver)
     {
         $resolver->setDefaults(array(
             'compound' => false,
+            'true_values' => array(1, '1', true, 'true'),
+            'false_values' => array(0, '0', false, 'false'),
         ));
     }
 }
diff --git a/tests/Form/DataTransformer/BooleanTypeToBooleanTransformerTest.php b/tests/Form/DataTransformer/BooleanTypeToBooleanTransformerTest.php
index 651f3df..fa260d7 100644
--- a/tests/Form/DataTransformer/BooleanTypeToBooleanTransformerTest.php
+++ b/tests/Form/DataTransformer/BooleanTypeToBooleanTransformerTest.php
@@ -3,7 +3,6 @@
 namespace FSevestre\BooleanFormTypeTest\Form\DataTransformer;
 
 use FSevestre\BooleanFormType\Form\DataTransformer\BooleanTypeToBooleanTransformer;
-use FSevestre\BooleanFormType\Form\Type\BooleanType;
 
 /**
  * @author Florent SEVESTRE
@@ -12,21 +11,21 @@ class BooleanTypeToBooleanTransformerTest extends \PHPUnit_Framework_TestCase
 {
     public function testTransformNull()
     {
-        $transformer = new BooleanTypeToBooleanTransformer();
+        $transformer = new BooleanTypeToBooleanTransformer(array(1, '1', true, 'true'), array(0, '0', false, 'false'));
 
         static::assertFalse($transformer->transform(null));
     }
 
     public function testTransformTrue()
     {
-        $transformer = new BooleanTypeToBooleanTransformer();
+        $transformer = new BooleanTypeToBooleanTransformer(array(1, '1', true, 'true'), array(0, '0', false, 'false'));
 
         static::assertTrue($transformer->transform(true));
     }
 
     public function testTransformFalse()
     {
-        $transformer = new BooleanTypeToBooleanTransformer();
+        $transformer = new BooleanTypeToBooleanTransformer(array(1, '1', true, 'true'), array(0, '0', false, 'false'));
 
         static::assertFalse($transformer->transform(false));
     }
@@ -38,7 +37,7 @@ public function testTransformFailed($value)
     {
         $this->setExpectedException('Symfony\Component\Form\Exception\TransformationFailedException');
 
-        $transformer = new BooleanTypeToBooleanTransformer();
+        $transformer = new BooleanTypeToBooleanTransformer(array(1, '1', true, 'true'), array(0, '0', false, 'false'));
         $transformer->transform($value);
     }
 
@@ -58,7 +57,7 @@ public function getTransformFailedData()
 
     public function testReverseTransformNull()
     {
-        $transformer = new BooleanTypeToBooleanTransformer();
+        $transformer = new BooleanTypeToBooleanTransformer(array(1, '1', true, 'true'), array(0, '0', false, 'false'));
 
         static::assertFalse($transformer->reverseTransform(null));
     }
@@ -68,7 +67,7 @@ public function testReverseTransformNull()
      */
     public function testReverseTransformTrue($value)
     {
-        $transformer = new BooleanTypeToBooleanTransformer();
+        $transformer = new BooleanTypeToBooleanTransformer(array(1, '1', true, 'true'), array(0, '0', false, 'false'));
 
         static::assertTrue($transformer->reverseTransform($value));
     }
@@ -77,7 +76,7 @@ public function getReverseTransformTrueData()
     {
         return array_map(function($value) {
             return array($value);
-        }, BooleanType::$TRUE_VALUES);
+        }, array(1, '1', true, 'true'));
     }
 
     /**
@@ -85,7 +84,7 @@ public function getReverseTransformTrueData()
      */
     public function testReverseTransformFalse($value)
     {
-        $transformer = new BooleanTypeToBooleanTransformer();
+        $transformer = new BooleanTypeToBooleanTransformer(array(1, '1', true, 'true'), array(0, '0', false, 'false'));
 
         static::assertFalse($transformer->reverseTransform($value));
     }
@@ -94,14 +93,14 @@ public function getReverseTransformFalseData()
     {
         return array_map(function($value) {
             return array($value);
-        }, BooleanType::$FALSE_VALUES);
+        }, array(0, '0', false, 'false'));
     }
 
     public function testReverseTransformFailed()
     {
         $this->setExpectedException('Symfony\Component\Form\Exception\TransformationFailedException');
 
-        $transformer = new BooleanTypeToBooleanTransformer();
+        $transformer = new BooleanTypeToBooleanTransformer(array(1, '1', true, 'true'), array(0, '0', false, 'false'));
         $transformer->transform('');
     }
 }
diff --git a/tests/Form/Type/BooleanTypeTest.php b/tests/Form/Type/BooleanTypeTest.php
index cc20788..9b21e18 100644
--- a/tests/Form/Type/BooleanTypeTest.php
+++ b/tests/Form/Type/BooleanTypeTest.php
@@ -2,7 +2,6 @@
 
 namespace FSevestre\BooleanFormTypeTest\Form\Type;
 
-use FSevestre\BooleanFormType\Form\Type\BooleanType;
 use Symfony\Component\Form\Test\TypeTestCase;
 
 /**
@@ -27,7 +26,7 @@ public function getFormTypeTrueData()
     {
         return array_map(function($value) {
             return array($value);
-        }, BooleanType::$TRUE_VALUES);
+        }, array(1, '1', true, 'true'));
     }
 
     /**
@@ -48,7 +47,7 @@ public function getFormTypeFalseData()
         return array_merge(
             array_map(function($value) {
                 return array($value);
-            }, BooleanType::$FALSE_VALUES),
+            }, array(0, '0', false, 'false')),
             array(array(null), array(''))
         );
     }