This article examines how stressful life events relate to the occurrence of illness in a nonclinical random sample of adolescents and what processes intervene in this relationship. Three alternative models of the life events and illness relationship are compared. Data support a "direct stress and illness model" as opposed to either a "sick role behavior model" or a "mental health model." Social support from parents appears to mediate the life events-illness relationship. Undesirable and ambiguous life events have more impact on illness than desirable events. Results are discussed in terms of adolescence as a unique developmental stage.