Leading explanations for ethnic disparities in U.S. women's employment derive largely from research on men. Although recent case studies of newer immigrant groups suggest that these explanations may be less applicable than previously believed, no study to date has assessed this question systematically. Using 2000 Census data, this study tests the relative merit of existing explanations for women in 12 ethnic groups. To this end, we disaggregate Hispanic, Asian and Middle Eastern women by country of origin and examine patterns by nativity. The results show that human capital and nativity are important for all groups, but these factors explain the employment gap with whites for Hispanic women much more than for Asian and Middle Eastern women, especially immigrants. Additionally, standard models are more useful for understanding variations in employment among Middle Eastern, Japanese and Hispanic women than for explaining differences among whites and other Asian subgroups. These findings indicate the need for newer concepts and measures to capture the increasing heterogeneity in U.S. ethnic women's employment patterns. We conclude by suggesting possible avenues for future research that expand on models of men's employment to include factors unique to women. (Contains 3 tables and 7 notes.)