Uncontrolled population growth may create many problems that hamper the growth of a city. The Family Planning Association, formed in 1950, has introduced many successful promotional campaigns to curb unwanted births. Well-known examples include the "Two is Enough" Campaign launched in 1975 and the "Mr. Able Male Involvement" Campaign, in 1986. The idea of a nuclear family of four, a perfect fit for a projected modern city of Hong Kong, gradually emerged and gained popularity.