Driven by new computer and digital fabrication tools, the architectural designs that are built are pushing boundaries of form, customization and construction. Pushed by practices wanting (and needing) to produce novelty, computer-aided design systems are increasingly parametric, that is, they represent designs that change with their input data. Such systems give more control and capability to designers, but require much more comprehensive understanding if they are to be used effectively. There is an imperative to master the complex set of ideas behind the new parametric computer-aided design systems.These ideas are not easy, at least for those with typical design backgrounds. Mastering them requires skill as designer, mathematician and computer scientist. Yet some of the best designers are developing stunning skill in evoking the new and surprising.This book teaches what the new knowledge and skill is that designers need to master the parametric and how they can learn and use it. It demonstrates clearly how using patterns to think about and work with parametric modeling helps designers master the new complexity imposed on them by the parametric modeling systems.