Eighty-nine consecutive admissions with primary depressive illness were prospectively ascertained and diagnosed in 1965-66 by R. E. Kendell, who also allocated each a position on a neurotic-psychotic continuum on the basis of previous discriminant function analysis. In 1983-84, 94% of the survivors were personally interviewed by a psychiatrist blind to index admission data. Operational outcome criteria were employed and longitudinal data were established for 98% of the series. Mortality risk was doubled overall, and increased sevenfold for women under 40 years at index admission. Less than one-fifth of the survivors had remained well, and over one-third of the series suffered unnatural death or severe chronic distress and handicap. Patients whose index episode marked their first psychiatric contact had a 50% chance of readmission within their lifetime, but those with previous admissions had a 50% chance of readmission within three years. Readmissions occurred even after 12 years of being symptom-free, and conversely patients recovered after as long as 15 years of illness. There was a high incidence of other disorders (schizoaffective disorder, alcoholism, schizophrenia), and only four patients showed pure recurrent unipolar histories. Patients at the psychotic end of the continuum were more likely to be readmitted and to have very poor outcomes.