This book is about emerging models of design that are just beginning to be used by ID types. They are based on constructivist and chaos (non-linear systems or "soft systems") theory. This book provides constructivist instructional design (C-ID) theorists with an opportunity to present an extended version of their design model. After an introductory chapter on the history of instructional design models, and a chapter on the guiding principles of C-ID, the creators of six different C-ID models introduce and explain their models. A final chapter compares the models, discusses the future of C-ID models, and discusses the ways constructivist designers and scholars can interact with, and work with, instructional technologists who use different paradigms.