The determinants of hours worked for employed women in developing countries is a little-studied topic. We compare the determinants of employment with the determinants of hours worked for prime-aged urban Brazilian women with and without husbands present. Given employment status, we find systematic differences for women in couple-headed and female-headed households. For the former, the same variables that affect employment do a good job of explaining hours worked. In contrast, our model generally fails to capture determinants of variation in hours worked for women who are sole heads of households. Sample selectivity functions in opposite directions for the two groups.