The Isle of Man is a self-governing British Crown Dependency situated equidistantly from England, Scotland and Ireland. In 1991, its population of ∼75,000 comprised ∼50% indigenous Manx and 50% immigrants, mainly from the surrounding countries. It was invited to join the European Longitudinal Study of Pregnancy and Childhood. The aim of the study was to enrol all pregnant women resident on the Island with an expected date of delivery in the 18-month period of January 1991-June 1992. A total of 1314 livebirths formed the eligible cohort. Questionnaires were completed by mothers and their partners during pregnancy and subsequently at 6 weeks, 6 months, 18 months, 3, 5, 7 and 15/16 years. Hands-on examination of the children occurred at age 7 years, when biological samples were collected. Teachers completed questionnaires at 7 and 15 years; medical records were extracted for the obstetric and childhood periods. Response rates varied from >80% from teachers and children at 15 years to only 23% from partners when their children were aged 7 years. Selected data sets are available to collaborators, although many of the data need funds for further collaboration.