Specific forms of maternal social support were analyzed for their relationship to a validated measure of home stimulation (the Inventory of Home Stimulation). The 69 study families were chosen to represent a wide variability of social support at the time of the child's birth. All index children had been discharged from a neonatal intensive care unit 3 years before the study. The overall Maternal Social Support Index (MSSI) developed for the study explained a significant (p < .01) amount of variance in the home stimulation of 3-year-olds after income, race, maternal age, and other possible confounding variables had been controlled. In addition, specific MSSI items were strongly associated with various forms of environmental stimulation. The data suggest that augmentation of specific aspects of mothers' social support networks may increase their children's informal learning opportunities.