RNA processing plays a critical role in realizing the full potential of a given genome. One means of achieving protein diversity is through RNA editing. A diverse array of editing events has been characterized, affecting gene expression in organisms from viruses and single cell parasites to humans and plants. The variety of editing mechanisms has required the development of many different experimental approaches, many of which are likely to be broadly applicable, particularly given the interplay between editing and other cellular processes, including transcription, splicing, and RNA silencing. RNA Editing not only covers most of the principal methods employed in the field, but also offers innovative solutions to the significant challenges posed by these experimental systems.