Maternity and family leave policies enable mothers to take time off work to prepare for and recover from childbirth and to care for their new children. While there is substantial variation in the details of these policies around the world, the existing research yields the following general conclusions. First, despite important barriers to the take-up of leave, both the implementation of new programs and extensions of existing ones increase leave-taking rates among new parents. Second, leave entitlements less than one year in length can improve job continuity for women and increase their employment rates several years after childbirth; longer leaves can negatively influence women’s earnings, employment, and career advancement. Third, extensions in existing paid leave policies have no impact on measures of child well-being, but the introduction of short paid and unpaid leave programs can improve children’s short- and long-term outcomes. Fourth, while more research is needed, the current evidence shows minimal impacts of existing U.S. state-level programs on employer-level outcomes such as employee productivity, morale, profitability, turnover rates, or the total wage bill.