This article is about social intervention research. A general definition of intervention is any interference that would modify a process or situation. In social work, interventions are intentionally implemented change strategies which aim to impede or eradicate risk factors, activate and/or mobilize protective factors, reduce or eradicate harm, or introduce betterment beyond harm eradication; thus social work intervention encompasses a range of psychotherapies, treatments, and programs. Interventions may be simple or complex. Yet simple interventions may have multiple elements that contribute to their effectiveness. Although social intervention research is an essential aspect of social work as a profession and research discipline, it is clearly multidisciplinary in its nature. The current knowledge base of social intervention research draws on knowledge gained from a wide variety of behavioral, psychological, and health interventions as well as from disciplines as diverse as psychology, education, medicine, public health, social work and other caring sciences. Social intervention research is vital to social work practice as professional decisions should be informed by evidence of both the potential benefits and harms of alternative interventions. Social intervention research focuses on the effects of an intervention under study. Of primary importance is understanding changes in the health and well-being of a target population. Subsequent results are then, ideally, used for decisions on future service provision. The goal of social intervention research is to bring about change in individuals, groups, or entire communities, and requires research methods that are most appropriate for achieving this goal.