A total of 1330 patients in an acute patients' therapeutic community ward were treated in 1977-1991. Their 2384 treatment episodes were analyzed, mainly 1-6 episodes per patient. The median length of hospitalization for all episodes was 40 days; during the first episode it was 39 days, during the 2nd 46 days, the 3rd 49 days, the 4th 48 days, the 5th 33 days and the 6th 47 days. The residents with a better immediate outcome usually stayed 10-20 days longer in hospital than those with an inferior outcome. The associations of length of hospitalization with some predictor variables were analyzed by a linear regression model. A long stay was associated with young age, a psychosis-level diagnosis, and active, motivated participation in individual and milieu therapy. Although economic reasons and expansion of the outpatient care may favor a short stay policy, some motivated borderline and psychosis patients seem to benefit from an individually timed inpatient experience in the therapeutic community setting.