This article focuses on the introduction of hydrofluocarbon (HFC) and hydrofluoroolefin (HFO) refrigerants in developed countries as a result of regulations requiring the phaseout of the production of hydrochlorofluorocarbons (HCFC). It discusses the global warming potential of HFOs, proposed regulation on HCFCs in the U.S., Canada and Mexico, and other alternatives to HCFCs refrigerants.