In this article for the "Highlights of 2024" series, we discuss antibody-drug conjugates (ADCs), which are an emerging class of targeted cancer therapies that harness the specificity of monoclonal antibodies to deliver cytotoxic agents directly to tumor cells. ADCs bind to tumor-associated antigens, undergo internalization via receptor-mediated endocytosis, and release their cytotoxic payload intracellularly, reducing systemic toxicity. This highly selective mechanism has led to significant advancements in oncology, improving treatment efficacy while minimizing adverse effects.