Contemporary digital design practice is in a state of rapid evolution. While architects have employed computer-aided drafting (CAD) systems for decades, only recently have two distinct and potent design sensibilities – parametric and algorithmic design – emerged. Nurtured by early architectural researchers and programmers operating in practice, these methodologies are now gaining widespread professional and academic acceptance. However, there remains considerable confusion about the meaning of the two terms, and about the meaning of ‘parametric design’ in particular. This article attempts to clarify the situation.