This book presents the recent developments in immunomodulatory biomaterials for cell-based therapies in various diseases, including diabetes, cancer, cardiovascular disease, and bone regeneration. The authors first cover the fundamentals of conventional immunology and immunomodulation, before focusing on the history, advantages, and challenges of cell therapies. Biological cell therapy has gained immense attention for various diseases due to unique advantages it has over chemical drugs regarding cost, ease of production, toxicity, and therapeutic efficacy. However, these cell-based therapies need an inert delivery system that can locally deliver cells and minimally elicit foreign body response. The book discusses the foreign body response to the immunomodulatory biomaterials as well as the current and future strategies for potential mitigation of considerable immune responses toward immunomodulatory biomaterials and devices.