The spread of drug resistant malaria is a potent threat to human health in much of the developing world. Resistance can be tracked and quantified provided we know the mutations responsible for resistance (true in many cases) and these data form the basis for many key genetic surveillance programmes aimed at ensuing the continued provision of effective drugs. The requisite malaria genetic data can, in principle, be obtained from analysing infected human blood samples but people are often simultaneously infected by several malaria clones and this makes it impossible to clearly identify the genetic composition of any single clone. We propose a program of research to develop and refine suitable methodologies that can overcome these problems of data interpretation allowing good quality genetic data on the frequency of drug resistance to inform public health policy. These methods of analysis also have more general application in understanding the genetic epidemiology of malaria transmission.