The relationship between severity of illness and psychologic adjustment was evaluated in 46 children with asthma. Two measures of the severity of asthma were used: the first, a composite objective measure based on clinical history and the second, parental estimates of the severity of their child's illness. Psychologic adjustment was measured by the Health Resources Inventory, a parental report of childhood behavior. Parental estimates of severity were correlated significantly with the objective measure of severity (r = .39; P less than .01), although a concordance value of 54% indicated marked lack of agreement between parental and objective ratings. As a group, children in this study achieved apparently normal adjustment scores, although scores ranged widely across all categories of severity. Children whose parents ranked their asthma as mild or severe had significantly lower adjustment scores (F = 3.28; P less than .05) than did those children rated by their parents as having moderate asthma. Children's ranks on the composite objective measure of severity were not associated with their adjustment scores, although children with greater use of medication had lower adjustment scores than did children with little or moderate medication use (P less than .05). The relationship of severity of illness to psychologic adjustment is complex. Children at all levels of severity may demonstrate problems of adjustment, suggesting that attention to psychologic risk should not be limited only to children with severe asthma.