This book contains selected articles from PRO-VE'02, the third working conference on Infrastructures for Virtual Enterprises, which was sponsored by the International Federation for Information Processing (IFIP) and held in Sesimbra, Portugal in May 2002. The included articles represent relevant examples of the current state of the art in virtual enterprises and other collaborative and networked organizations, and provide valuable insights on future trends and challenges. The book contents clearly reflect a growing maturation and diversification of the area. Important development directions are well represented, such as: modeling and reference architectures, formation of virtual organizations, including contract management and negotiation, operation support functionalities, infrastructures and interoperability, virtual communities and new collaboration forms, best practices and strategic planning, economic aspects and performance metrics, training and new ways of working.