The nature of stress is reviewed in its role of producing physical illness and mental maladaptations with an emphasis on physician's morbidity from both. A review of existing studies indicates that physicians compare favorably with the general population in mortality from physical illness but unfavorably with regard to mental illness, notably the affective, suicide and addiction. The definition of illness is examined with relation to stress, physical and psychosocial. It is accepted that disease presupposes the existence of special vulnerability. In mental illness, however, the vulnerability stems from inner sources. In the doctor this consists of a neuroticism originating in the fear of death which has motivated him to become a physician in the first place. A study of the writer supports these theoretical assumptions. It is proposed that the neuroticism thus created facilitates various degrees of maladaptive patterns. It is, however, also a direct effect of negative personality features created by it in the first place. Stress of medical practice does influence the emotional adjustment but does not seem to exert a greater negative influence on the physical health of doctors than does stress encountered in other occupations. This may be due to the better car physicians are able to secure for themselves.