Traditionally, parents and families in Papua New Guinea (PNG) were not concerned about ideal family size, birth spacing or sex composition of children. Most people still believe in large families for continuation of lineages and clan memberships for gaining attachment to land. Having many children was also desirable for agriculture and tribal security. But these beliefs and practices are changing with urbanisation and modernisation. Many factors are responsible for these changes, although ‘social practices and behaviour protecting the health of mothers and children were prevalent in most traditional cultures of PNG’. Using data from the 1996 and 2006 PNG Demographic and Health Surveys (DHS), and qualitative data collected in 2011, this chapter examines fertility preferences among women and men of reproductive ages and the factors influencing such preferences. The chapter provides recommendations for policies to reduce fertility through changes in couples’ preference for large family sizes.