Statistical profiles of Mexican American women workers and a narrative describing their role in trade unions illustrate the economic precariousness of this group and of women in general. Census and Labor Department reports document national labor trends from 1930-1980 with emphasis on the Southwest. Tables present information on occupational type, median income, and educational level for Mexican American, Anglo, Black, and American Indian women and for Mexican American and Anglo men. Among findings discussed are that: (1) Mexican American and American Indian women have the lowest median incomes in the Southwest; (2) Anglo and Mexican American men have higher median incomes than any group of women; and (3) women with more years of schooling have higher median incomes and employment rates. The overview of Mexican American women in industry and unions examines ethnic and sexual discrimination, gives examples of Mexican American women's labor militancy and analyzes the impact of mechanization, undocumented workers, and seasonal work. Discussion points out that women who must work to support their families may consider job security their top priority. The final topic is the role of Mexican American women as policy makers in two unions--United Cannery, Agricultural, Packing, and Allied Workers of America (UCAPAWA) and United Farm Workers. (JHZ)