Mothers are shown to receive lower wages than childless women across industrial countries. Although research on mothers' wage disadvantage has noted that the extent of this disadvantage is not universal among mothers, it has paid relatively little attention to how the structural characteristics of jobs moderate the price women pay for motherhood. Using data from 16 waves of the National Longitudinal Survey of Youth that began in 1997, we examine how the pay gap between mothers and non-mothers varies by occupational characteristics. Deriving hypotheses from three prominent explanations for the motherhood wage penalty--stressing work-family conflict and job performance, compensating differentials, and employer discrimination, respectively--we test whether this penalty changes with an occupation's exposure to hazardous conditions, schedule regularity, required on-the-job training, competitiveness, level of autonomy, and emphasis on teamwork. Results from fixed-effects models show that the wage reduction for each child is less in occupations with greater autonomy and lower teamwork requirements. Moreover, mothers encounter a smaller penalty when their occupations impose less competitive pressure. On the whole, these findings are consistent with the model focusing on job strain and work-family conflict, adding evidence to the importance of improving job conditions to alleviate work-family conflict. [ABSTRACT FROM AUTHOR]