diff --git a/src/mat.rs b/src/mat.rs
index 31a8835..7a869e3 100644
--- a/src/mat.rs
+++ b/src/mat.rs
@@ -33,11 +33,21 @@ pub trait Matrix<T,V>: Dimensional<V>, ToPtr<T>, Eq, Neg<self> {
      */
     static pure fn identity() -> self;
     
+    /**
+     * Sets the matrix to the identity matrix
+     */
+    fn to_identity(&mut self);
+    
     /**
      * Returns a matrix with all elements set to zero
      */
     static pure fn zero() -> self;
     
+    /**
+     * Sets each element of the matrix to zero
+     */
+    fn to_zero(&mut self);
+    
     /**
      * Returns the scalar multiplication of this matrix and `value`
      */
@@ -259,6 +269,11 @@ pub impl<T:Copy Float> Mat2<T>: Matrix<T, Vec2<T>> {
                   _0, _1)
     }
     
+    #[inline(always)]
+    fn to_identity(&mut self) {
+        *self = Mat2::identity();
+    }
+    
     /**
      * Returns the additive identity matrix
      * ~~~
@@ -277,6 +292,11 @@ pub impl<T:Copy Float> Mat2<T>: Matrix<T, Vec2<T>> {
                   _0, _0)
     }
     
+    #[inline(always)]
+    fn to_zero(&mut self) {
+        *self = Mat2::zero();
+    }
+    
     #[inline(always)]
     pure fn mul_t(&self, value: T) -> Mat2<T> {
         Mat2::from_cols(self[0].mul_t(value),
@@ -570,6 +590,11 @@ pub impl<T:Copy Float> Mat3<T>: Matrix<T, Vec3<T>> {
                   _0, _0, _1)
     }
     
+    #[inline(always)]
+    fn to_identity(&mut self) {
+        *self = Mat3::identity();
+    }
+    
     /**
      * Returns the additive identity matrix
      * ~~~
@@ -591,6 +616,11 @@ pub impl<T:Copy Float> Mat3<T>: Matrix<T, Vec3<T>> {
                   _0, _0, _0)
     }
     
+    #[inline(always)]
+    fn to_zero(&mut self) {
+        *self = Mat3::zero();
+    }
+    
     #[inline(always)]
     pure fn mul_t(&self, value: T) -> Mat3<T> {
         Mat3::from_cols(self[0].mul_t(value),
@@ -974,6 +1004,11 @@ pub impl<T:Copy Float Sign> Mat4<T>: Matrix<T, Vec4<T>> {
                   _0, _0, _0, _1)
     }
     
+    #[inline(always)]
+    fn to_identity(&mut self) {
+        *self = Mat4::identity();
+    }
+    
     /**
      * Returns the additive identity matrix
      * ~~~
@@ -998,6 +1033,11 @@ pub impl<T:Copy Float Sign> Mat4<T>: Matrix<T, Vec4<T>> {
                   _0, _0, _0, _0)
     }
     
+    #[inline(always)]
+    fn to_zero(&mut self) {
+        *self = Mat4::zero();
+    }
+    
     #[inline(always)]
     pure fn mul_t(&self, value: T) -> Mat4<T> {
         Mat4::from_cols(self[0].mul_t(value),
diff --git a/src/test/test_mat.rs b/src/test/test_mat.rs
index 1dca40c..806f448 100644
--- a/src/test/test_mat.rs
+++ b/src/test/test_mat.rs
@@ -9,6 +9,9 @@ fn test_Mat2() {
                    y: Vec2 { x: 2f, y: 4f } };
     let b = Mat2 { x: Vec2 { x: 2f, y: 4f },
                    y: Vec2 { x: 3f, y: 5f } };
+    
+    let mut mut_a = a;
+    
     let v1 = Vec2::new(1f, 2f);
     let f1 = 0.5f;
     
@@ -29,6 +32,19 @@ fn test_Mat2() {
     
     assert a.col(0) == Vec2::new(1f, 3f);
     assert a.col(1) == Vec2::new(2f, 4f);
+    
+    assert Mat2::identity() == Mat2::new(1f, 0f,
+                                         0f, 1f);
+    mut_a.to_identity();
+    assert mut_a.is_identity();
+    mut_a = a;
+    
+    assert Mat2::zero() == Mat2::new(0f, 0f,
+                                     0f, 0f);
+    
+    mut_a.to_zero();
+    assert mut_a == Mat2::new(0f, 0f,
+                              0f, 0f);
 
     assert a.determinant() == -2f;
     assert a.trace() == 5f;
@@ -105,6 +121,9 @@ fn test_Mat3() {
     let b = Mat3 { x: Vec3 { x: 2f, y: 5f, z:  8f },
                    y: Vec3 { x: 3f, y: 6f, z:  9f },
                    z: Vec3 { x: 4f, y: 7f, z: 10f } };
+    
+    let mut mut_a = a;
+    
     let v1 = Vec3::new(1f, 2f, 3f);
     let f1 = 0.5f;
     
@@ -136,6 +155,21 @@ fn test_Mat3() {
     assert a.col(0) == Vec3::new(1f, 4f, 7f);
     assert a.col(1) == Vec3::new(2f, 5f, 8f);
     assert a.col(2) == Vec3::new(3f, 6f, 9f);
+    
+    assert Mat3::identity() == Mat3::new(1f, 0f, 0f,
+                                         0f, 1f, 0f,
+                                         0f, 0f, 1f);
+    mut_a.to_identity();
+    assert mut_a.is_identity();
+    mut_a = a;
+    
+    assert Mat3::zero() == Mat3::new(0f, 0f, 0f,
+                                     0f, 0f, 0f,
+                                     0f, 0f, 0f);
+    mut_a.to_zero();
+    assert mut_a == Mat3::new(0f, 0f, 0f,
+                              0f, 0f, 0f,
+                              0f, 0f, 0f);
 
     assert a.determinant() == 0f;
     assert a.trace() == 15f;
@@ -228,6 +262,9 @@ fn test_Mat4() {
                    y: Vec4 { x: 2f, y: 3f, z:  2f, w:  2f },
                    z: Vec4 { x: 1f, y: 2f, z:  3f, w:  3f },
                    w: Vec4 { x: 0f, y: 1f, z:  1f, w:  0f } };
+    
+    let mut mut_a = a;
+    
     let v1 = Vec4::new(1f, 2f, 3f, 4f);
     let f1 = 0.5f;
     
@@ -273,6 +310,24 @@ fn test_Mat4() {
     assert a.col(1) == Vec4::new(2f, 6f, 10f, 14f);
     assert a.col(2) == Vec4::new(3f, 7f, 11f, 15f);
     assert a.col(3) == Vec4::new(4f, 8f, 12f, 16f);
+    
+    assert Mat4::identity() == Mat4::new(1f, 0f, 0f, 0f,
+                                         0f, 1f, 0f, 0f,
+                                         0f, 0f, 1f, 0f,
+                                         0f, 0f, 0f, 1f);
+    mut_a.to_identity();
+    assert mut_a.is_identity();
+    mut_a = a;
+    
+    assert Mat4::zero() == Mat4::new(0f, 0f, 0f, 0f,
+                                     0f, 0f, 0f, 0f,
+                                     0f, 0f, 0f, 0f,
+                                     0f, 0f, 0f, 0f);
+    mut_a.to_zero();
+    assert mut_a == Mat4::new(0f, 0f, 0f, 0f,
+                              0f, 0f, 0f, 0f,
+                              0f, 0f, 0f, 0f,
+                              0f, 0f, 0f, 0f);
 
     assert a.determinant() == 0f;
     assert a.trace() == 34f;