Advances in physiological psychology and neuroendocrinology, together with epidemiological studies, have added new dimensions to psychosomatic research. Psychological influences still are accepted as exacerbators or trigger mechanisms, if less often as causes. Theories of psychosomatics which connected specific personality profiles with specific psychosomatic illnesses have lost favor, and multifactorial explanations, which include heredity, environment, social class, life stress, endocrines, brain areas, neurohormones, and immunological mechanisms, are new areas of research. Research methods have become more sophisticated scientifically, particularly in the selection and size of samples tested, and the variety of situations investigated. Psychological reactions to illness in general, terminal disease, and death, and psychological experiences of pain, in addition to variable effects of psychotherapeutic methods and psychotherapists' personality, are identifiable but unquantified influences which seem acceptable as contributors to, if not causes of, psychophysiological disorders.