This volume is the second in a series on depressive illness. The first volume, entitled Phenomenology of Depressive Illness, is de voted to a description of depressive illness from many vantage points including that of the patient as well as the psychiatrist. Epidemiological, nosological, and developmental aspects are included together with specific descriptions of major subtypes of depressive illness. It is only after an illness is fully described that an attempt should be made to generate models with ex planatory and predictive properties. This second volume is that next step. The major...