The History of Unigraphics, 1974–2001

Unigraphics was a first-generation commercial computer-aided design and manufacturing (CAD/CAM) system, initially released by United Computing Corporation in 1974. This article provides a firsthand account of the evolution of Unigraphics from 1974 through 2001, during which authors Paul Sicking, George Allen, and Wil Valenzuela were members of the development group. The authors describe the motivations behind each major step in the evolution of Unigraphics as well as the underlying technical strategies. The article also highlights some of the distinctive aspects of the organization’s culture and the continuity of leadership that helped navigate challenging product transitions despite changes in corporate ownership. Although this article only covers the period until 2001, Unigraphics continued to evolve thereafter with a different brand identity (NX), which is still a leading CAD/CAM product, now developed by Siemens Digital Industries Software.