Children and youth with medical complexity are a diverse group with uncommon diagnoses, a spectrum of needs and varying access to supports. Although this population represents a small proportion of all children, their unique needs lead to substantial use of healthcare services. With its first pan-Canadian report on children and youth with medical complexity, the Canadian Institute for Health Information examined how this population uses healthcare services. Key findings include the wide variation in the rate of medical complexity among children and youth across Canada. Children and youth with medical complexity were found to require a high proportion of hospital and emergency department care; however, their readmission rates were found to be lower than that of the general pediatric population.