The impact of an accumulation of sociocontextual stress on children's social skill development was examined among 167 predominantly African American mothers and their 2-year-old children. Two theoretical models were considered. First, based on Rutter's (1979) cumulative risk approach, an accumulation of stress was hypothesized to moderate the impact of sensitive parenting on change in social skills such that the protective effects of sensitive parenting declined when cumulative stress reached a critical threshold. Second, based on a family stress model approach, an accumulation of stress was expected to indirectly affect social skills by way of sensitive parenting; that is, sensitive parenting was expected to explain or mediate any direct links between cumulative stress and children's social skills. Results were only consistent with the moderational hypothesis. Contrary to expectations, sensitive parenting predicted increases in social skills from age 2 to 4 only under conditions of the highest cumulative stress.