diff --git a/Source/OpenTK/Math/Vector2.cs b/Source/OpenTK/Math/Vector2.cs
index ebfc8101..da08ae5a 100644
--- a/Source/OpenTK/Math/Vector2.cs
+++ b/Source/OpenTK/Math/Vector2.cs
@@ -885,6 +885,41 @@ namespace OpenTK
 
         #endregion
 
+        #region Transform
+
+        /// <summary>
+        /// Transforms a vector by a quaternion rotation.
+        /// </summary>
+        /// <param name="vec">The vector to transform.</param>
+        /// <param name="quat">The quaternion to rotate the vector by.</param>
+        /// <returns>The result of the operation.</returns>
+        public static Vector2 Transform(Vector2 vec, Quaternion quat)
+        {
+            Vector2 result;
+            Transform(ref vec, ref quat, out result);
+            return result;
+        }
+
+        /// <summary>
+        /// Transforms a vector by a quaternion rotation.
+        /// </summary>
+        /// <param name="vec">The vector to transform.</param>
+        /// <param name="quat">The quaternion to rotate the vector by.</param>
+        /// <param name="result">The result of the operation.</param>
+        public static void Transform(ref Vector2 vec, ref Quaternion quat, out Vector2 result)
+        {
+            Quaternion v = new Quaternion() { X = vec.X, Y = vec.Y, Z = 0, W = 0 };
+            Quaternion i;
+            Quaternion t;
+            Quaternion.Invert(ref quat, out i);
+            t = i * v;
+            v = t * quat;
+
+            result = new Vector2(v.X, v.Y);
+        }
+
+        #endregion
+
         #endregion
 
         #region Operators
diff --git a/Source/OpenTK/Math/Vector2d.cs b/Source/OpenTK/Math/Vector2d.cs
index 48794668..98c6dfd4 100644
--- a/Source/OpenTK/Math/Vector2d.cs
+++ b/Source/OpenTK/Math/Vector2d.cs
@@ -773,6 +773,41 @@ namespace OpenTK
 
         #endregion
 
+        #region Transform
+
+        /// <summary>
+        /// Transforms a vector by a quaternion rotation.
+        /// </summary>
+        /// <param name="vec">The vector to transform.</param>
+        /// <param name="quat">The quaternion to rotate the vector by.</param>
+        /// <returns>The result of the operation.</returns>
+        public static Vector2d Transform(Vector2d vec, Quaterniond quat)
+        {
+            Vector2d result;
+            Transform(ref vec, ref quat, out result);
+            return result;
+        }
+
+        /// <summary>
+        /// Transforms a vector by a quaternion rotation.
+        /// </summary>
+        /// <param name="vec">The vector to transform.</param>
+        /// <param name="quat">The quaternion to rotate the vector by.</param>
+        /// <param name="result">The result of the operation.</param>
+        public static void Transform(ref Vector2d vec, ref Quaterniond quat, out Vector2d result)
+        {
+            Quaterniond v = new Quaterniond() { X = vec.X, Y = vec.Y, Z = 0, W = 0 };
+            Quaterniond i;
+            Quaterniond t;
+            Quaterniond.Invert(ref quat, out i);
+            t = i * v;
+            v = t * quat;
+
+            result = new Vector2d(v.X, v.Y);
+        }
+
+        #endregion
+
         #endregion
 
         #region Operators
diff --git a/Source/OpenTK/Math/Vector3.cs b/Source/OpenTK/Math/Vector3.cs
index c3c85c09..a34584de 100644
--- a/Source/OpenTK/Math/Vector3.cs
+++ b/Source/OpenTK/Math/Vector3.cs
@@ -1094,6 +1094,37 @@ namespace OpenTK
             result = v4.Xyz;
         }
 
+        /// <summary>
+        /// Transforms a vector by a quaternion rotation.
+        /// </summary>
+        /// <param name="vec">The vector to transform.</param>
+        /// <param name="quat">The quaternion to rotate the vector by.</param>
+        /// <returns>The result of the operation.</returns>
+        public static Vector3 Transform(Vector3 vec, Quaternion quat)
+        {
+            Vector3 result;
+            Transform(ref vec, ref quat, out result);
+            return result;
+        }
+
+        /// <summary>
+        /// Transforms a vector by a quaternion rotation.
+        /// </summary>
+        /// <param name="vec">The vector to transform.</param>
+        /// <param name="quat">The quaternion to rotate the vector by.</param>
+        /// <param name="result">The result of the operation.</param>
+        public static void Transform(ref Vector3 vec, ref Quaternion quat, out Vector3 result)
+        {
+            Quaternion v = new Quaternion() { X = vec.X, Y = vec.Y, Z = vec.Z, W = 0 };
+            Quaternion i;
+            Quaternion t;
+            Quaternion.Invert(ref quat, out i);
+            t = i * v;
+            v = t * quat;
+
+            result = new Vector3(v.X, v.Y, v.Z);
+        }
+
         /// <summary>Transform a Vector3 by the given Matrix, and project the resulting Vector4 back to a Vector3</summary>
         /// <param name="vec">The vector to transform</param>
         /// <param name="mat">The desired transformation</param>
diff --git a/Source/OpenTK/Math/Vector3d.cs b/Source/OpenTK/Math/Vector3d.cs
index a5557c32..d924395b 100644
--- a/Source/OpenTK/Math/Vector3d.cs
+++ b/Source/OpenTK/Math/Vector3d.cs
@@ -1090,6 +1090,37 @@ namespace OpenTK
             result = v4.Xyz;
         }
 
+        /// <summary>
+        /// Transforms a vector by a quaternion rotation.
+        /// </summary>
+        /// <param name="vec">The vector to transform.</param>
+        /// <param name="quat">The quaternion to rotate the vector by.</param>
+        /// <returns>The result of the operation.</returns>
+        public static Vector3d Transform(Vector3d vec, Quaterniond quat)
+        {
+            Vector3d result;
+            Transform(ref vec, ref quat, out result);
+            return result;
+        }
+
+        /// <summary>
+        /// Transforms a vector by a quaternion rotation.
+        /// </summary>
+        /// <param name="vec">The vector to transform.</param>
+        /// <param name="quat">The quaternion to rotate the vector by.</param>
+        /// <param name="result">The result of the operation.</param>
+        public static void Transform(ref Vector3d vec, ref Quaterniond quat, out Vector3d result)
+        {
+            Quaterniond v = new Quaterniond() { X = vec.X, Y = vec.Y, Z = vec.Z, W = 0 };
+            Quaterniond i;
+            Quaterniond t;
+            Quaterniond.Invert(ref quat, out i);
+            t = i * v;
+            v = t * quat;
+
+            result = new Vector3d(v.X, v.Y, v.Z);
+        }
+
         /// <summary>
         /// Transform a Vector3d by the given Matrix, and project the resulting Vector4 back to a Vector3
         /// </summary>
diff --git a/Source/OpenTK/Math/Vector4.cs b/Source/OpenTK/Math/Vector4.cs
index dcf756b1..9b09ee76 100644
--- a/Source/OpenTK/Math/Vector4.cs
+++ b/Source/OpenTK/Math/Vector4.cs
@@ -942,6 +942,37 @@ namespace OpenTK
                 vec.X * mat.Row0.W + vec.Y * mat.Row1.W + vec.Z * mat.Row2.W + vec.W * mat.Row3.W);
         }
 
+        /// <summary>
+        /// Transforms a vector by a quaternion rotation.
+        /// </summary>
+        /// <param name="vec">The vector to transform.</param>
+        /// <param name="quat">The quaternion to rotate the vector by.</param>
+        /// <returns>The result of the operation.</returns>
+        public static Vector4 Transform(Vector4 vec, Quaternion quat)
+        {
+            Vector4 result;
+            Transform(ref vec, ref quat, out result);
+            return result;
+        }
+
+        /// <summary>
+        /// Transforms a vector by a quaternion rotation.
+        /// </summary>
+        /// <param name="vec">The vector to transform.</param>
+        /// <param name="quat">The quaternion to rotate the vector by.</param>
+        /// <param name="result">The result of the operation.</param>
+        public static void Transform(ref Vector4 vec, ref Quaternion quat, out Vector4 result)
+        {
+            Quaternion v = new Quaternion() { X = vec.X, Y = vec.Y, Z = vec.Z, W = vec.W };
+            Quaternion i;
+            Quaternion t;
+            Quaternion.Invert(ref quat, out i);
+            t = i * v;
+            v = t * quat;
+
+            result = new Vector4(v.X, v.Y, v.Z, v.W);
+        }
+
         #endregion
 
         #endregion
diff --git a/Source/OpenTK/Math/Vector4d.cs b/Source/OpenTK/Math/Vector4d.cs
index 2072813b..23f0e6c6 100644
--- a/Source/OpenTK/Math/Vector4d.cs
+++ b/Source/OpenTK/Math/Vector4d.cs
@@ -945,6 +945,37 @@ namespace OpenTK
                 vec.X * mat.Row0.W + vec.Y * mat.Row1.W + vec.Z * mat.Row2.W + vec.W * mat.Row3.W);
         }
 
+        /// <summary>
+        /// Transforms a vector by a quaternion rotation.
+        /// </summary>
+        /// <param name="vec">The vector to transform.</param>
+        /// <param name="quat">The quaternion to rotate the vector by.</param>
+        /// <returns>The result of the operation.</returns>
+        public static Vector4d Transform(Vector4d vec, Quaterniond quat)
+        {
+            Vector4d result;
+            Transform(ref vec, ref quat, out result);
+            return result;
+        }
+
+        /// <summary>
+        /// Transforms a vector by a quaternion rotation.
+        /// </summary>
+        /// <param name="vec">The vector to transform.</param>
+        /// <param name="quat">The quaternion to rotate the vector by.</param>
+        /// <param name="result">The result of the operation.</param>
+        public static void Transform(ref Vector4d vec, ref Quaterniond quat, out Vector4d result)
+        {
+            Quaterniond v = new Quaterniond() { X = vec.X, Y = vec.Y, Z = vec.Z, W = vec.W };
+            Quaterniond i;
+            Quaterniond t;
+            Quaterniond.Invert(ref quat, out i);
+            t = i * v;
+            v = t * quat;
+
+            result = new Vector4d(v.X, v.Y, v.Z, v.W);
+        }
+
         #endregion
 
         #endregion