Nuclear receptor coregulators are molecules required for efficient function of nuclear receptors. The field of nuclear receptor coregulators has experienced remarkably rapid growth since its inception in the mid-1990s. With this growth has emerged a complex and often redundant nomenclature, which, although relatively familiar to those within the immediate field, has the potential to generate confusion as coactivators and corepressors come under increasing scrutiny in other, less familiar disciplines. We discuss this issue with reference to some specific examples and proffer some guidelines to the community for identifying these molecules.