This is a clinical practice guideline for adult and child patients with cancer. The guideline provides an overview of fertility preservation options for adult males, adult females, and children. Patient education and referral to reproductive specialists prior to cancer treatment are also discussed. Methods of fertility preservation are compared including cryopreservation options, hormonal therapy, and ovarian transposition (oophoropexy). Outcomes of interest include cost and effectiveness of preservation techniques, and effects of cancer treatments on fertility.