In the United States, 10% of all adolescents suffer from a chronic illness (Blum, 1992; Krementz, 1989; Millstein & Litt, 1990). In total, approximately one million children have a chronic illness that affects daily life (Perrin & MacLean, 1988) and another ten million have somewhat less serious physical illnesses (Haggerty, 1984). A chronic illness is defined as “one that lasts for a substantial period of time or that has sequelae that are debilitating for a long period of time” (Perrin, 1985, p. 2). Chronic illnesses are associated with a wide range of sequelae and impairment including pain and discomfort, school absences, activity disruptions, poorer social competence, higher use of medication and health care visits, as well as increased risk for both internalizing and externalizing problems (e.g., Cadman, Boyle, Szatmari, & Offord, 1987; Gortmaker, Walker, Weitzman, & Sobel, 1990; Jackson & Vessey, 2004).