Book excerpt: Measuring the social and economic costs of violence can be difficult, and most estimates only consider direct economic effects, such as productivity loss or the use of health care services. Communities and societies feel the effects of violence through loss of social cohesion, financial divestment, and the increased burden on the healthcare and justice systems. Initial estimates show that early violence prevention intervention has economic benefits. The IOM Forum on Global Violence Prevention held a workshop to examine the successes and challenges of calculating direct and indirect costs of violence, as well as the potential cost-effectiveness of intervention.