Working in a stressful environment increases the risk both of suffering physical illness or symptoms of psychological distress (Cooper and Cartwright 1994; Cooper and Payne 1988), and also work-related accidents and injuries (Sutherland and Cooper 1991). The substantive body of well-documented research evidence supporting a causal relationship between working conditions, both physical and psychosocial, and individual health and well-being, has legitimised the concept of stress-induced illness and disease. Although it has received less academic interest, there is also research evidence supporting causal links between stressful working conditions and greater accident involvement in various contexts, including company car drivers (Cartwright et al. 1996), transit operators (Greiner et al. 1998), medical practitioners (Kirkcaldy et al. 1997) and veterinary surgeons (Trimpop et al. 2000).
In an increasingly litigious society, recent years have seen a growing number of ‘cumulative trauma’ compensation claims against US employers (National Institute of Occupational Safety and Health (NIOSH) 1986); Karasek and Theorell 1990), and later, a number of successful personal injury claims in the United Kingdom (Earnshaw and Cooper 2001). The concept of ‘cumulative trauma’ relates to the development of mental illness as a result of continual exposure to occupational stress; the California Labor Code states that workers are entitled to compensation for disability or illness caused by ‘repetitive mentally or physically traumatic activities extending over a period of time, the combined effect of which causes any disability or need for medical treatment’. In the United Kingdom, the legal implications of stress-induced personal injury were highlighted by the landmark case of Walker v Northumberland County Council (see Box 1.1).