The present study investigated the effects of divorce and family relations on young children's development prospectively, using an ethnically diverse sample of approximately 300 low-income families. We also were able to examine the moderating effects of ethnicity on child adjustment in always two-parent, to-be-divorced, already-divorced, and always single-parent families. Results indicated that to-be-divorced European American and African American families demonstrated higher rates of preschool-age behavior problems, and already-divorced families showed similar trends. Parental conflict and behavior problems accounted for predivorce differences in child behavior problems, whereas rejecting parenting accounted for differences in problem behavior between always single-parent and always two-parent families. The results are discussed in terms of the importance of ethnicity in influencing young, low-income children's adjustment to different family structures.