["Population and Development Review, Volume 47, Issue 4, Page 913-964, December 2021. ", "\nAbstract\nIn the course of the twentieth century, social scientists and policy analysts have produced a large volume of literature on whether policies boost fertility. This paper describes the results of a systematic review of the literature on the effects of policy on fertility since 1970 in Europe, the United States, Canada, and Australia. Empirical studies were selected through extensive systematic searches, including studies using an experimental or quasi‐experimental design. Thirty‐five studies were included, covering reforms of parental leave, childcare, health services, and universal child transfers. In line with previous reviews, we find that childcare expansions increase completed fertility, while increased cash transfers have temporary effects. New evidence on parental leave expansions, particularly from Central Europe, suggests larger effects than previously established. High‐earning couples benefit more from parental leave expansions, while expanding childcare programs can reduce social inequalities on other domains. Subsidizing assisted reproductive treatments shows some promise of increasing birth rates for women over the age of 35. Countries that to date have limited support for families can build on solid evidence if they choose to expand these programs.\n"]