Mechai Viravaidya (born 17 January 1941, Thai: มีชัย วีระไวทยะ; RTGS: Michai Wirawaithaya) is a former politician and activist in Thailand who promoted condoms, family planning and AIDS awareness in Thailand. Since the 1970s, Mechai has been affectionately known as "Mr. Condom", and condoms are often referred as "mechais" in Thailand. From the time that he began his work, the average number of children in Thai families has decreased from 7 to 1.5.
