It is now common practice in many hospitals to admit psychiatrically ill mothers along with their babies. Main first admitted a mother with her child in 1948, and started to admit puerperal cases in 1955. Since those days, there has been a piecemeal development of mother and baby facilities throughout the country. Service developments have usually been the result of local interest rather than central planning and motivated by the belief that such a service adds to the quality of care. We were aware that our hospital was not offering such a service and so we decided to look at what occurred elsewhere to help in our planning. We devised a questionnaire and sent this to 42 district medical officers in England and personally visited the mother and baby units at Park Prewett and Fairmile Hospitals. We received 29 replies to our questionnaire, a 69 per cent response rate. Most of these had been completed by an involved clinician or senior nurse and several expressed a wish to be informed of the findings.