Social work with offenders requires extensive knowledge of crime, criminal justice, life situations, and support systems. This textbook introduces the fundamentals, areas of work, tasks, and methodological approaches in a practical manner. A specific professional focus is significant for all the emergencies that arise from criminal behavior. It is essential to connect individual and socially related aspects with knowledge of deficient life situations as well as institutional and criminal policy dynamics. In line with this requirement, the textbook presents the essential foundations and tasks of social work with offenders and aims to raise awareness of the specific action requirements. It covers the central practice fields of offender assistance.