Patients with cystic fibrosis (CF) are now living longer, with a median survival of 32 years in 2000. With longer life expectancy and improved treatments for pulmonary disease, other complications of CF are becoming more apparent. The primary endocrine complications affecting adolescents with CF include (1) poor growth and pubertal development, (2) CF-related diabetes, and (3) poor bone mineralization. This chapter discusses pathophysiology, screening, and treatment of endocrine complications of CF.