With the increasing availability of adult cystic fibrosis clinics, pediatric caregivers are faced with deciding whether an adolescent is ready for transfer. Twenty-two pediatric caregivers, ten adult caregivers, and three adult patients were interviewed to determine what behaviors and knowledge they perceived as essential for successful transition to adult care. No differences were noted between the pediatric and adult caregivers' responses. Based on their responses, a 24-item questionnaire was developed to assess readiness for transfer of 36 adolescents with cystic fibrosis. The questionnaire scores were found to be better predictors than age for success in transfer to adult care. The questionnaire allows the pediatric staff to focus on those areas that adolescents may need further preparation.