diff --git a/src/vectors/vec3d.rs b/src/vectors/vec3d.rs
index 55cea8f..6b110fd 100644
--- a/src/vectors/vec3d.rs
+++ b/src/vectors/vec3d.rs
@@ -2,7 +2,7 @@ use std::cmp::Eq;
 // use std::collections::VecDeque;
 use std::fmt::Debug;
 use std::hash::Hash;
-use std::ops::{Add, /* Index, IndexMut, */ Mul, Sub};
+use std::ops::{Add, AddAssign, Mul, Sub, SubAssign};
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
 pub struct Vector3D<T> {
@@ -101,6 +101,14 @@ impl<T: Add + Add<Output = U>, U> Add for Vector3D<T> {
     }
 }
 
+impl<T: AddAssign> AddAssign for Vector3D<T> {
+    fn add_assign(&mut self, rhs: Self) {
+        self.x += rhs.x;
+        self.y += rhs.y;
+        self.z += rhs.z;
+    }
+}
+
 impl<T: Sub + Sub<Output = U>, U> Sub for Vector3D<T> {
     type Output = Vector3D<U>;
 
@@ -113,6 +121,14 @@ impl<T: Sub + Sub<Output = U>, U> Sub for Vector3D<T> {
     }
 }
 
+impl<T: SubAssign> SubAssign for Vector3D<T> {
+    fn sub_assign(&mut self, rhs: Self) {
+        self.x -= rhs.x;
+        self.y -= rhs.y;
+        self.z -= rhs.z;
+    }
+}
+
 impl<T: Mul + Mul<Output = U>, U> Mul for Vector3D<T> {
     type Output = Vector3D<U>;