Since the late 1960s Carnegie Mellon’s School of Architecture has been a leading research center in computer-aided design. In the 1970s researchers worked on models of design cognition, design automation, and design databases. This agenda bore fruit in the CAD software that has revolutionized design practice. In the 1980s and 1990s Carnegie Mellon was known for work on geometry, generative systems, and collaborative design. Today the Computational Design Laboratory continues in this tradition of building experimental systems to explore ideas at the intersection of computation and design.