Controversy continues about the underlying etiopathogenesis, diagnostic criteria, and recommendations for polycystic ovary syndrome (PCOS) in adolescents. Recent literature has recognized these deficiencies and evidence based expert recommendations have become more available. The purpose of this chapter is to offer primary care providers a practical understanding and approach to the diagnosis and treatment of PCOS in adolescents. Although the presence of polycystic ovary morphology (PCOM) is included as a key diagnostic criterion of PCOS in adults, it is currently not recommended for the diagnosis in adolescents. As such, the diagnosis of PCOS in adolescents currently hinges on evidence of ovulatory dysfunction and androgen excess. Recommended evidence of ovulatory dysfunction includes: consecutive menstrual intervals >90 days even in the first year after menstrual onset; menstrual intervals persistently <21 or >45 days 2 or more years after menarche; and lack of menses by 15 years or 2-3 years after breast budding. Recommended evidence of androgen excess include: moderate to severe hirsutism; persistent acne unresponsive to topical therapy; and persistent elevation of serum total and/or free testosterone level. Importantly, a definitive diagnosis of PCOS is not needed to initiate treatment. Treatment may decrease risk of future comorbidity even in the absence of a definitive diagnosis. Deferring diagnosis, while providing symptom treatment and regular/ frequent follow-up of symptomology, is a recommended option.The treatment options for PCOS should be individualized to the presentation, needs, and preferences of each patient. Goals of treatment are to improve quality of life and long-term health outcomes. Lifestyle modifications remain first-line management of overweight and obese adolescents with PCOS. Combined oral contraceptives (COC) are first line pharmacotherapy for management of menstrual irregularity and acne, and metformin is superior to COCs for weight reduction and improved dysglycemia. COCs and metformin have similar effects on hirsutism, but often need to be paired with other treatment modalities to achieve further improvement of cutaneous symptoms. Clinicians should be cognizant that PCOS is associated with significant metabolic and psychological comorbidity and screen for these issues appropriately.