The Cork BASELINE Birth Cohort Study (Babies After SCOPE: Evaluating the Longitudinal Impact on Neurological and Nutritional Endpoints) was established with three main objectives: to investigate the effects of intrauterine growth restriction and early nutrition on metabolic health and neurodevelopment; to ascertain the incidence and determinants of food allergy and eczema in early childhood; and to describe early infant feeding, supplementation and nutritional status and their effects on physical and neurological growth and health outcomes. The SCOPE Ireland pregnancy cohort formed the basis of recruitment of infants to BASELINE [n 1537] and an additional 600 infants were recruited after delivery providing a total sample of 2137 between 2008 and 2011. Assessments were at day 2 and at 2, 6, 12 and 24 months, with 5-year assessments ongoing. Blood and DNA samples were biobanked at 15 and 20 weeks' gestation, birth, 24 months and 5 years. Body composition data were collected at 2 days and 2 months (air-displacement plethysmography) and at 5 years (dual-energy X-ray absorptiometry). Trans-epidermal water loss was measured at 2 days, 2, 6 and 24 months. Detailed dietary and validated developmental assessments were conducted at 24 months. Researchers interested in collaboration can contact [email@example.com] and further information be found at [http://www.baselinestudy.net/ or http://www.birthcohorts.net/].