Objectives To document the extent to which maternity data are collected and how they are recorded, and to identify problems that may affect their availability throughout the NHS. Methods Postal survey in September 1997 with structured questionnaires. Setting 207 NHS trusts with maternity units in England. Participants Heads of midwifery in maternity units. Main outcome measures Extent to which maternity data were routinely recorded, how they were recorded and evaluated, and to whom they were made available. Results 167 (81%) of questionnaires were returned, representing 166 trusts. Of these trusts, 165 collected ≥ 17 of the 19 data items in HES maternity tail, and 158 collected ≥ 40 of the 45 items selected from Körner dataset. Only 18 collected all five items selected from the "indicators of success," and 17 did