This document discusses the diagnosis and management of adnexal masses. It provides information on the normal size and variation of ovaries and lifetime risk of ovarian neoplasms. Differential diagnoses of adnexal masses are outlined based on patient age. Diagnostic evaluation includes physical exam, ultrasound, CT or MRI if needed. Common ovarian tumors at different life stages are described. Functional cysts, endometriomas, benign and borderline tumors are discussed. Complications, clinical presentation, imaging and tumor markers are summarized. Guidelines for management of asymptomatic cysts and indications for surgery are provided.