A systematic review of 53 studies of the onset conditions revealed: (1) No symptoms were reported which were without psychological antecedents, although the level of the relationship between psychological antecedent and symptom was usually only moderate or weak; (2) the psychological antecedents, in order of rank with highest first, were resentment, frustration, depression, anxiety, and helplessness; (3) the special uniqueness of the review is in its systematic coverage of the "immediate-context" research (23 studies) and the comparison of those with a sample of "broad-context," mainly retrospective, research studies (30 studies). The same main types of psychological antecedents were reported by both types of studies with frequencies which were not significantly different except for frustration and separation. Frustration was more often reported in the immediate observation studies, separation more often in the broad-context studies. The review ends with suggestions of methods for understanding the mediation of psychological antecedents and symptoms. in a formal way, most family physicians and most patients could see at times a relationship between stressful experiences and the onset of certain somatic conditions. Much of the awareness of the relationship was lost to the medical profession around the turn of the century, when it became "scientific," but the topic was pursued in the research on psychosomatic medicine. The psychosomatic studies we have reviewed begin about 35 years ago in an era of uncontrolled observational methods. Studies of this kind have become increasingly sophisticated in research design. As we suggest later, not only were the early scientifically unsophisticated observations in accord with folk-belief, but also the more sophisticated research tended to confirm those earlier studies.Formal research on the onset of psy-