This book presents the clinical scope of cancer immunotherapeutic agents for solid tumors and Hematologic malignancies, elaborates on the scientific details of their modes of action, and presents the impact of these agents on oncology, patients and the broader healthcare system. At present, cancer immunotherapies fall broadly into three categories: immune checkpoint inhibitors (ICIs), adoptive T cell therapies, and cancer vaccines which have distinct mechanisms of action. Immune checkpoint inhibitors rely upon disrupting tumor antigen recognition as self by the immune system through inhibition of checkpoint molecules. Adoptive T cell therapies involve the engineering of T cells ex vivo to target and destroy tumor cells. The first part of this book will provide an overview of the discovery and mechanistic details of the technology. The second part will be devoted to elaborating on the clinical outcomes, successes and limitations for specific tumor subtypes, which includes bothsolid tumors and hematologic malignances for both pediatric and adult populations. As such, the book offers a valuable resource for oncologists, hematologists, and all those seeking an up-to-date overview of cancer immunotherapies.