Nearly 600 papers were located in citation and keyword searches regarding the effects of humidi-ty on comfort, health, and indoor environmental quality (IEQ). Of these, 69 papers reported the effects of low humidity (RH less than or equal to 40%) were analyzed in detail. For comfort, low humidity had little effect on thermal comfort, but increased skin dryness, eye irritation, and static electricity as humidity decreased. For some pathogens, such as influenza, lower humidity increased virus survival. Humidity effects on IEQ were mixed, with non-uniform effects of low humidity on volatile organic compound (VOC) emissions and indoor air quality. Temperature, ventilation rates, and time were noted as confounding variables. A majority of studies that used human subjects utilized exposure times of three hours or less with adult subjects; few studies used children, adolescents, or elderly subjects.