Eighty-three chronic obstructive bronchitic patients were psychologically assessed before being randomly allocated to 1 of 3 management regimes. The following measures were taken: psychiatric disturbance, personality, social-desirability response set, vocabulary, expectations about treatment, attitudes and beliefs about bronchitis, effect of patient's bronchitis on the family, work, self, physical exercise, smoking, and general health. Outcome was assessed after one month and again one year later, and the measures included physiological tests of lung functioning, an exercise tolerance test, reported symptoms, time off work, drop-out, and death. Contrary to expectations, it was found that psychological variables had some prognostic significance for outcome assessed by medical measures of illness severity. More important was the finding that, in bronchitics under retiring age, weeks off work during the year of the study could be predicted by psychological variables but not by physiological measures of illness severity.