In this chapter, normal foetal growth is described, starting from the embryonic period until delivery. Environmental and behavioural influences on growth are discussed, as is how these lead to abnormal growth patterns. An important subject is how growth should be measured and how normal deviations in size should be discerned from abnormal growth. One of the important learning goals is understanding the pathophysiological processes of excessive growth and restricted growth, as well as their impact on outcomes in the immediate period of pregnancy and in later life. This chapter discusses the large influence of maternal and paternal conditions, health and lifestyle on offspring health. Lastly, the evidence on interventions to improve outcomes is discussed.