The specific challenges of living with diabetes mellitus (DM) which the child and parent must confront at each developmental stage are identified from infancy through adolescence. This discussion is divided into four developmental stages: 1) DM in infancy (0-2 years of age); 2) DM in toddlers and preschoolers (2-5 years); 3) DM in the school-age child (6-11 years); and 4) DM during early- to mid-adolescence (12-16 years). The central milestones of normal psychosocial development are reviewed and a summary is provided of recent research at each developmental stage with an emphasis on clinical implications for pediatric diabetes care teams.