From 2000 to 2011 the longitudinal Pacific Island Families (PIF) Study has followed the growth and development of more than 1000 Pacific children since they were born at Middlemore Hospital, South Auckland. We know that by age 11 more than one out of four PIF children weighed more than 60kg and only one out of fifteen weighed less than 37kg, the weight of a reference child. The aim of this project is to investigate at 14 years, a critical time of rapid development, what determines the different rates of growth. Measurements of food and activity patterns, pubertal development, risks for diabetes and hypertension, the family and wider environment will identify relationships with objectively assessed body size, fatness and growth rate. Understanding past and present influences on child growth and health will inform timely interventions and policies to optimise health and reduce inequalities for Pacific peoples.