Asthma is the most common chronic illness among children in the United States and can impact nearly all aspects of functioning. Most research suggests that children with severe asthma display more emotional and behavioral problems than their healthy peers. These psychological difficulties are associated with increased risk for functional impairments and problematic disease course. Multidisciplinary teams that assess and treat these psychosocial factors using psychoeducational and behavioral interventions are important for children whose asthma is poorly controlled. Future research should examine the ways in which stress, emotions, and immune functions interact, so as to develop more preventative interventions.