This text provides one of the first book-length studies on the innovative and sustainable development of complex systems in the era of digital transformations, combining quantitative data from several countries with detailed qualitative accounts at the national level. In particular, the book covers the basic concepts, methods, and cutting-edge research on innovation and sustainability in complex systems. Given its scope, the book will be of great interest and value to researchers and practitioners working across the social sciences and in a diverse range of areas in complexity science. Pursuing a multidisciplinary approach, the book is also an ideal resource for advanced undergraduate and graduate level courses in complexity science, sustainability research, economics, and development studies.