I analyze the effects of paid parental leave on maternal labor supply. Using monthly longitudinal data from the Survey of Income and Program Participation, my event-study research design characterizes the evolution of labor-force participation around childbirth for women affected by paid leave laws in California and New Jersey. I find that paid leave laws are associated with a substantial increase in labor-force participation in the months directly around birth but have little impact beyond six months after birth. While US-style short-duration leave is unlikely to change prolonged exits from the labor force, my findings imply that paid leave laws induce some women to stay more attached, particularly low-skill women.