The field of antibody-drug conjugates (ADCs) has undergone remarkable advancements in recent years, marked by significant progress in both drug approvals and ongoing clinical development. Since the approval of the first ADC in 2010 (gemtuzumab ozogamicin, Mylotarg®), the landscape has expanded dramatically. Today, there are 11 FDA-approved ADCs, targeting a variety of cancers across multiple indications. The approved ADCs include a range of payloads, linkers, and antibodies, each optimized for a variety of specific therapeutic targets. The increasing diversity of ADCs reflects the growing potential of these innovative treatments to address a wide array of malignancies, from hematologic cancers to solid tumors. This book aims to provide a comprehensive overview of the current state of the ADC field including the latest developments, challenges, and emerging trends, comprising expertise from a broad range of disciplines from basic research, industry, clinical practice and regulatory affairs. We explore not only the scientific and technical aspects of ADC design—such as payloads, linkers, and antibody selection—but also the developmental hurdles and regulatory complexities that influence the success of ADCs in clinical practice. Real-world examples of ADCs that have made it from the lab to the clinic offer invaluable insights into the trials and triumphs that shape this dynamic field. It is our hope that this book will serve as both a valuable resource for experts in the field and an accessible introduction for those new to the exciting world of ADCs.