The main purpose of this study was to describe the characteristics of the social networks and social support of mothers of chronically ill children and adolescents. The data collected also allowed for the identification of the predisposing factors to receiving low social support among the mothers. Receipt of social support was assessed according to six dimensions: source of support, type of support, perceived need for support, satisfaction with the quality and the quantity of support, as well as most valued source of support. Results indicate that mothers wanted more support than they received, particularly in the areas of emotional, appraisal, and informative support. Furthermore, spouses, professionals, and immediate family members were identified by mothers as important sources of support. Discriminant analysis showed that the probability of receiving low support increased if the chronically ill child was an adolescent, the father had a higher level of education, and the family income was middle-low. Results are discussed in terms of the implications for intervention.