If social work is to fulfill its enormous tasks in the modern world, it requires science. This centuries-old insight has led to the emergence of social work as a science. Its concerns, its subject area, its international history, its philosophical and scientific theoretical foundation, as well as its ethical principles, classify it as a human science. This book presents its development and foundations, while also arguing that social work is and remains a necessary science. The discussions are based on the definition of social work by the International Federation of Social Workers (IFSW). According to this definition, the science of social work is tasked with providing engaged knowledge (assessment, intervention) for addressing social problems (to promote social change, of prob.