This analysis uses March Current Population Survey data from 1999-2010 and a differences-in-differences approach to examine how California's first in the nation paid family leave (PFL) program affected leave-taking by mothers following childbirth, as well as subsequent labor market outcomes. We obtain robust evidence that the California program more than doubled the overall use of maternity leave, increasing it from around three to six or seven weeks for the typical new mother -with particularly large growth for less advantaged groups. We also provide suggestive evidence that PFL increased the usual weekly work hours of employed mothers of one-to-three year-old children by 6 to 9% and that their wage incomes may have risen by a similar amount. The United States is the only advanced industrialized country without a national law providing new mothers (and often fathers) with entitlements to paid family leave (PFL).However, three states have implemented paid leave programs, the first of these being California, where PFL took effect in 2004. We study how California's program has affected leave-taking by mothers following childbirth, and the extent to which these effects differ across population subgroups. We are particularly interested in learning whether PFL has reduced previous disparities in leave-taking, whereby advantaged mothers have been much more likely to use leave than their less advantaged counterparts. We also provide an initial investigation of the medium-term impacts on mothers' labor market outcomes: employment, work hours, and wage income.The analysis uses March Current Population Survey data from 1999-2010 and a differences-in-differences (DD) approach to compare pre-versus post-program implementation experiences of mothers with infants or young children -the treatment groups -to control groups alternatively consisting of women with older children, childless women, men with non-infant children, or new mothers in other states. 1 We obtain robust evidence that the California program increased leave-taking, more than doubling overall maternity leave use -increasing it from around 3 to 6 or 7 weeks -with particularly large growth for less advantaged mothers (those who are less educated, unmarried, or nonwhite) who had relatively low levels of baseline use. This contrasts starkly with the results for other state family leave laws (most of which extend rights to unpaid leave beyond those in the FMLA), where the estimated effects are much larger for college-educated and married women than for less advantaged counterparts (Han, Ruhm and Waldfogel, 2009). The exploration of effects on medium-term labor market outcomes provides 1 We considered men with infant children as a treatment group, since such fathers are covered under PFL, but did not find consistent evidence of effects on leave-taking. This may have occurred because low rates of paternity leave use imply that we did not have the power to detect statistically significant effects.Page 2 more equivocal results, but with evidence that paid fami...