A total of 60 infants and toddlers with SCD and 60 matched normally-developing peers between the ages of birth and three years served as subjects in a five-year longitudinal design in order to permit between-group comparisons. Subjects were assessed at regularly scheduled intervals with a variety of developmental (e.g., Bayley), cognitive (e.g., Stanford-Binet), neuropsychological (e.g., Purdue Pegboard), family functioning, and physiological indices in order to delineate those factors in the SCD group that were associated with decreased cognitive and academic performance. A unique and important feature of this research was the inclusion of magnetic resonance imaging technology. These techniques made it possible to study in a comprehensive and componential manner the neuroanatomical effects of SCD instead of relying on any single instrument or assessment to document this phenomenon. Goals of this study included the identification of: (a) specific areas of learning deficiencies in children with SCD; (b) the period in which these deficiencies began to occur; and (c) the relationship between types of learning deficits and various outcome measures. In sum, this study helped to determine how these factors interacted and changed over time as the child with SCD matured, the disease fluctuated, and the family and/or the environmental context changed in relation to cognitive development.