Insect repellents are an important part of almost everyone’s lives. Approximately 40% of Americans and 200 million people in the world use N,N-diethyl-meta-toluamide (DEET). A variety of insect repellents, both synthetic and natural, are available for use including DEET, picaridin, IR3535, oil of citronella, p-menthane-3,8-diol (PMD)/oil of lemon eucalyptus (OLE), 2-undecanone, and catnip oil, and others. Insect repellents are important in repelling vector-borne diseases including dengue viruses, Eastern equine encephalitis, yellow fever, and Zika virus. Insect repellents come in various forms (e.g., spray-on, wipe, lotion, cream, gel, clip-on, candles, torches, coils), and label directions should be followed to ensure their safe use. This chapter discusses the use, production, exposure, and potential health effects of several of the major insect repellents that are currently in use. It also addresses some of the myths that exist surrounding repellent use.