An approach to socio-technical HCI called Human Work Interaction Design (HWID) emerged around 2005. It has grown steadily, and now is the time for sharing this research with a wider audience. In this book, the HWID approach is used to discuss socio-technical HCI theory, cases, methods, and impact. The book introduces HWID as a multi-sided platform for theorizing about socio-technical HCI work design in the digital age. It presents design cases that illustrate the design of socio-technical relations, provides specific advice for researchers, consultants, and policy makers, and reflects on the open issues related to theorizing about sociotechnical HCI.