This book constitutes the refereed proceedings of the Second International Workshop on Cooperative Buildings, CoBuild'99, held in Pittsburgh, PA, USA in October 1999. The 15 revised full papers presented together with two short papers, two posters, and one demo were carefully reviewed and selected from a total of 33 submissions. The book is divided in chapters on integrated workplace design and architecture, critical technologies, meeting and conference environments, infrastructure, methodology and empirical studies, and networked home environments.