Avoidable mortality is a selection of causes of death considered to be amenable to health care and thereby used as an indicator of the quality of health care. In this study avoidable mortality for more than 30,000 psychiatric patients discharged from any hospital of Stockholm County between 1981 and 1985 has been followed up in the Cause of Death Register for the period 1986-1990. Standardised rate ratios were calculated for different groups of psychiatric disorders compared to the general population of Stockholm County for indicators of avoidable mortality, suicide, other mortality ("unavoidable") and causes possibly related to treatment with psychotrophic drugs. As expected, the psychiatric patients had the most pronounced elevated risk for suicide. i.e. 6- to 24-fold compared to the general population, and noticeably more elevated for women. It is also noteworthy that the relative mortality risks for diagnoses amenable to medical interventions and potential side-effects of psychotrophic drugs are higher than for other causes of death ("unavoidable"). The relative risks for avoidable mortality were 4.7 for men and 3.8 for women and for diagnoses possibly related to side-effects of psychotrophic drugs, 7.2. The relative risks for "unavoidable" mortality were 3.4 for men and 3.2 for women. The excess avoidable mortality rates for psychiatric patients and the elevated suicide risk, especially for female patients, are warning signals of shortcomings in psychiatric care that warrants further investigation.