Background surveys of microwave ovens and literature related to the potential health hazards of microwave radiation were performed by the Radiation Protection Bureau, of Health and Welfare of Canada, to determine if there was a need for statutory regulations to control such devices. Sufficient evidence was obtained to indicate that standards of design, construction and functioning were required to ensure safety to the general population. Consequently, in 1974, the Microwave Oven Regulations were promulgated under the Radiation Emitting Devices Act of Canada. Earlier, similar microwave oven performance standards were adopted in Japan in 1970 and in the United States in 197I. The introduction of the Regulations appears to have had a marked effect by causing improved oven designs, and better manufacturing and testing procedures, resulting in substantial reductions of leakage radiation from the ovens. This paper summarizes the regulatory requirements, highlights the problems encountered in conducting the oven surveys and provides data on the number of models tested and their compliance status in Canada.