Architects use computer-aided tools to help them visualize their ideas and build models of their designs. However, the majority of these models are built in such a way that it makes them difficult to modify interactively. Parametric design software addresses this problem by allowing architects to specify relationships among various parameters of their design model. The advantage is that a designer can then change a few parameters and the remainder of the model will react and update accordingly and in a consistent manner based on the pre-set associative rules. Through a detailed description of various parametric, generative, and algorithmic techniques, this book provides a practical guide to generating geometric and topological solutions for various situations, including explicit step-by-step tutorials that will enable the reader to understand both general concepts and specific computational algorithms. While the techniques and algorithms can be generalized to suit to any parametric environment, the book illustrates its concepts using the scripting languages of one of the most powerful 3D visualization and animation design software systems (Autodesk 3ds Max MAXScript), one of the most popular open-source Java-based scripting environments (Processing), and a brand new language specifically tailored for parametric and generative design (Autodesk DesignScript). This clear, accessible book will have a wide appeal to students who would like to experiment more with parametric techniques but lack the skills and knowledge to do so. Includes a foreword by Robert Woodbury and an afterword by Brian Johnson.