This chapter provides a comprehensive understanding about social work intervention and emphasizes the importance, types, theories, approaches, and processes of social work interventions. Generally, individuals, groups, and communities require intervention by professional social workers. Practitioners and social workers working at different levels are committed to providing professional services (social work services) and enhancing the capacity of their clients through social work intervention, where social workers play significant and improved roles, and relevant and appropriate techniques to deal with their clients. Timely and appropriate intervention not only ensures the solving of the problems of the client but also brings positive growth and development. Socio-economic, political, and ecological phenomena have brought new challenges and problems that cause under-development at the global level. Certain situations and circumstances emphasize the importance of social work intervention [SWI]. Effective social work interventions made by professional social workers can bring positive outcomes and solutions. This chapter also advocates how social workers provide appropriate social work intervention or social work services skillfully to individuals, groups, organizations, and communities. It also seeks new areas where social workers can test the interventional methods and skills.