The rise of non-communicable diseases and their impact in low- and middle-income countries has gained increased attention in recent years. However, the explanation for this rise is mostly an extrapolation from the history of high-income countries whose experience differed from the development processes affecting today's low- and middle-income countries. This review appraises these differences in context to gain a better understanding of the epidemic of non-communicable diseases in low- and middle-income countries. Theories of developmental and degenerative determinants of non-communicable diseases are discussed to provide strong evidence for a causally informed approach to prevention. Health policies for non-communicable diseases are considered in terms of interventions to reduce population risk and individual susceptibility and the research needs for low- and middle-income countries are discussed. Finally, the need for health system reform to strengthen primary care is highlighted as a major policy to reduce the toll of this rising epidemic. © 2008 Blackwell Publishing Ltd.