diff --git a/Engine/source/math/mQuat.h b/Engine/source/math/mQuat.h
index 2ea1b94c1..ca6ed5d82 100644
--- a/Engine/source/math/mQuat.h
+++ b/Engine/source/math/mQuat.h
@@ -227,8 +227,8 @@ inline F32 QuatF::dot( const QuatF &q ) const
 
 inline F32 QuatF::angleBetween( const QuatF & q )
 {
-   // angle between to quaternions
-   return mAcos(x * q.x + y * q.y + z * q.z + w * q.w);
+   // angle between two normalized quaternions.
+   return mAcos(q.dot(*this)) * 2.0f;
 }
 
 #endif // _MQUAT_H_