One hundred mothers of babies aged under 15 weeks who attended well baby clinics were rated for the presence of emotional disorders by health visitors. These assessments were compared with the mothers' scores on the General Health Questionnaire (GHQ), a screening instrument for identifying psychiatric cases in the general population. The results indicate that symptoms of minor psychiatric disorder are a problem for an appreciable number of postpartum women, although the health visitors showed a misclassification rate of roughly 40%. It is suggested that routine screening using the questionnaire at the time of the baby's six week check would both improve the detection rate and also enable the health visitors to give extra support to those mothers who were most in need of it.