1953: Chinese leaders suggest that the population should be controlled and approve a law on contraception and abortion, but the plan is stranded by political upheaval and the 1959-1961 famine.
1970: Chinese population exceeds 800 million.
1975: China adopts the slogan "Late, Long and Few" and encourages couples to have one child and urges them to have no more than two.
1980: The Communist Party says every couple should have only one child. A new marriage law says couples are obligated to practice family planning, placing a de facto limit of one child for each family.
1984: China adjusts the policy, allowing a second child for some families in rural areas and for couples who both are an only child, and in some other specified circumstances.
2001: China decrees new laws to better manage the administration of the policy, including penalties for unapproved births. The laws allow local government to impose fines for additional children.
2013: China adds an exemption allowing two children for families in which one parent, rather than both, is an only child.
Sources: China's National Population and Family Planning Commission and Xinhua News Agency