Essential Mathematics for Computational Design introduces to design professionals the foundation mathematical concepts that are necessary for effective development of computational methods for 3D modeling and computer graphics. This is not meant to be a complete and comprehensive resource, but rather an overview of the basic and most commonly used concepts. The material is directed towards designers who have little or no background in mathematics beyond high school. All concepts are explained visually using Grasshopper® (GH), the generative modeling environment for Rhinoceros® (Rhino).