The methods of evolutionary genetics are critically important for the analysis and interpretation of the massive datasets on DNA sequence variation and evolution that are becoming available, as well for our understanding of evolution in general. This book shows readers how models of the genetic processes involved in evolution are made (including natural selection, migration, mutation, and genetic drift in finite populations), and how the models are used to interpret classical and molecular genetic data. The material is intended for advanced level undergraduate courses in genetics and evolutionary biology, graduate students in evolutionary biology and human genetics, and researchers in related fields who wish to learn evolutionary genetics. The topics covered include genetic variation, DNA sequence variability and its measurement, the different types of natural selection and their effects (e.g. the maintenance of variation, directional selection, and adaptation), the interactions between selection and mutation or migration, the description and analysis of variation at multiple sites in the genome, genetic drift, and the effects of spatial structure. The final two chapters demonstrate how the theory illuminates our understanding of the evolution of breeding systems, sex ratios and life histories, and some aspects of genome evolution.