Generation R is an ongoing prospective cohort study of child development from the prenatal period through young adulthood in a multi-ethnic population recruited from the Rotterdam, Netherlands metropolitan area. The study enrolled 9,778 mothers with a delivery date between April 2002 and January 2006; they had 9,749 live births. The primary objective of the study is to identify early environmental and genetic determinants of normal and abnormal growth, development, and health through young adulthood to inform strategies for improving health and delivery of healthcare for pregnant women and children. Areas of research include maternal health, growth and physical development, behavioral and cognitive development, asthma and atopy, infectious and inflammatory diseases in childhood, and health and healthcare.

Data is collected during several phases of growth: pregnancy and birth, 0 to 4 years old ("preschool period"), 5 years old, 9 years old, 13 years old, and 17 years old. Measures and data collected throughout the course of the study include physical examinations, questionnaires, ultrasound examinations, biological samples, behavioral observations, allergy tests, MRI images, cardiac stress tests, cognitive tests, and electroencephalograms (EEG).