Directed to a broad and interdisciplinary audience, this book provides a complete account of what has been accomplished in applied and systemic-structural activity theory. It presents a new approach to applied psychology and the study of human work that has derived from activity theory. The selected articles demonstrate the basic principles of studying human work and particularly computer-based work in complex sociotechnical systems. The book includes examples of applied and systemic-structural activity theory to HCI and man-machine-systems, aviation, safety, design and optimization of human performance.