Understanding mechanisms of gene regulation that are independent of the DNA sequence itself – epigenetics – has the potential to overthrow long-held views on central topics in biology, such as the biology of disease or the evolution of species. High throughput technologies reveal epigenetic mechanisms at a genome-wide level, giving rise to epigenomics as a new discipline with a distinct set of research questions and methods. Leading experts from academia, the biotechnology and pharmaceutical industries explain the role of epigenomics in a wide range of contexts, covering basic chromatin biology, imprinting at a genome-wide level, and epigenomics in disease biology and epidemiology. Details on assays and sequencing technology serve as an up-to-date overview of the available technological tool kit. A reliable guide for newcomers to the field as well as experienced scientists, this is a unique resource for anyone interested in applying the power of twenty-first-century genomics to epigenetic studies.