Genetic Epidemiology is defined by an amalgam of methods garnered from traditional epidemiology, population and family-based epidemiology, from statistics, and importantly, from bioinformatics. Together, specific aspects of these disciplines are applied to the study of genes and environment, and of gene environment interactions. Both quantitative and qualitative traits may be of interest. Genetic epidemiology uses unique case-control, family, and population-based designs, and genotyping from multiple sources. Our goal has been to learn about genetic susceptibility to disease and genetic determinants of therapeutic responsiveness. A full series in genetic epidemiology is offered in The Johns Hopkins Bloomberg School of Public Health.