Androgen insensitivity syndrome (AIS) is an undervirilization syndrome in individuals with 46, XY karyotype. The undervirilization can be complete feminization or incomplete virilization with grades of ambiguity. AIS is caused by mutations in the androgen receptor, resulting in resistance to the physiologic activities of androgens. Differing degrees of resistance lead to three phenotypes: a complete form with female-appearing external genitalia, a partial form with a wide range of virilization, and a mild form with only minor undervirilization. AIS presents different challenges depending on whether resistance is complete or partial. Challenges include sex assignment, which impacts other medical decisions such as gonadectomy, hormonal replacement, and other surgical interventions. This review describes medical, psychosocial, and ethical concerns for each stage of development in complete and partial AIS, from the neonatal period to adulthood. These aspects of care should be addressed within an ethical framework by a multidisciplinary team, with the patients and families being the stakeholders in the decision-making process. We use the GRADE system when appropriate to appraise the existing evidence and provide recommendations and guidelines for management of AIS and appropriate transition of patients from pediatric to adult care.