This article reviews the research literature on the business value that can be achieved when employers and organizations offer critical incident response (CIR) services. CIR services are frequently provided as requested by corporations, insurers, and as a specialty service from Employee Assistance Programs (EAPs). There is a significant body of applied research conducted over the past 20 years worldwide that offers considerable empirical evidence to support the clinical effectiveness of CIR and related “psychological first aid” kinds of workplace services. In contrast, there are far fewer research studies available to examine the business case for CIR. A search of the literature obtained a small number of employer case studies conducted in the 1990s and several newer investigations of CIR services that are integrated with other behavioral health and benefit management programs. The research available indicates that CIR services can offer financial savings and business value, primarily from reducing disability and workers' compensation claims and improving the rate and success of employee return to work after a critical event. Six employers' case studies are presented. Although the available evidence is promising, the rare event nature of the conditions that create the need for CIR services and their delivery in applied settings combine to offer significant challenges to conducting scientific investigations of the business impact of these services. More high-quality research is needed before firm conclusions can be drawn about the nature of business outcomes in this area. [ABSTRACT FROM AUTHOR]