Women who showed new psychiatric morbidity after a 30-month follow-up of a random community sample of New Zealand women were compared with those who were free of psychiatric disorder at follow-up. There were 25 new cases among the 215 women who were originally not psychiatric cases and who were re-interviewed. Using the weighted back population data to obtain prevalence figures for the general population, 6.9% became new cases over the two and a half years. Those who developed psychiatric disorder initially showed more psychiatric symptoms at a subdiagnostic level. Baseline factors that preceded the onset of psychiatric disorder were being separated or divorced, coming from a large family, having poor social networks, living alone, having few social role responsibilities such as paid employment or motherhood, and having poor physical health. An additional cross-sectional association at follow-up was poor financial security. Good social networks were closely linked with the number of a woman's social roles and appeared to protect her against the onset of psychiatric disorder. Consistent with the initial cross-sectional study, the follow-up data provide no support for marriage and child-care being risk factors for female psychiatric disorder. However, in New Zealand, these factors indicate social integration and are associated with superior mental health.