Contemporary outcome measures of chronic illnesses such as type 1 diabetes mellitus are broader than those clinical outcomes traditionally assessed in therapeutic encounters. A holistic approach emphasises quality of life and emotional well-being as well as the achievement of optimal disease management. This paper reviews current knowledge about growth, metabolic control, diabetes complications, neurocognitive and psychological outcomes as well as health-related quality of life in childhood diabetes mellitus. It is suggested that the antecedents of adverse diabetes and psychological outcomes in adolescence lie in the years prior to adolescence. The model of care in childhood diabetes mellitus must be focussed on earlier screening and intervention if adverse outcomes are to be reduced.