177 cases of parapartum mental illness and 173 matched obstetric controls were studied retrospectively from the perspective of the social welfare services (SWS). Data covering five years before the index partus until five to seven years thereafter, were studied. Parapartum mentally ill women were known to the SWS to a much greater extent (75%) than their matched controls (33%). They also presented more severe environmental problems than their matched controls. Within the index sample the largest number of adverse factors known to the SWS was found in the addicts and NTI (neuroses and temporary insufficiencies) groups. The dysfunction in the families appeared to be constant throughout the observation period. A large proportion of the index children (32%) had been placed in foster care or adopted. When the index women had applied to the SWS during the first postpartum year the social workers were informed of the fact that she had contacted a psychiatric department in 8 out of 10 cases. However, only in half of these cases had regular collaboration taken place. Collaboration was far more frequent when the mother suffered from severe mental illness than when she was suffering from a less severe mental disturbance.