Over recent decades there has emerged a significant literature regarding the effects of development and globalisation on the culture of Pacific Islanders. It often has emphasised the alarming rate at which non-communicable diseases and related health complications have increased, presumably due to changes in lifestyles. The aim of this thesis is to report on a research project that investigated the contradictory effects that globalisation and development have had on the people of Tonga, particularly in respect to their way of life and how they negotiate the relationship between tradition and modernity. It is informed by a period of ethnographic fieldwork undertaken by the researcher with three families in Tonga, as well as unstructured interviews with members of the Tongan community in Tonga and New Zealand. The study especially explores the link between the shift away from traditional lifeways and increasing ill health, with a focus on the link between diabetes and diet, and more generally Tongan understandings of ‘health’ and non-communicable diseases and their treatments.