The use of multiple agent chemotherapy and combined modality treatment of childhood and adolescent cancers has markedly increased survival rates. Thus, the majority of young cancer patients survive into adulthood and the potential long-term consequences of the therapies are of ongoing concern. Alkylating agents have proven to be the most toxic to the ovaries; however radiation is also extremely gonadotoxic. In addition, combination of these modalities will produce additive effects in terms of ovarian damage (follicle depletion). As a result, there are increasing numbers of young cancer survivors with impaired or absent gonadal function. Advances in the field of assisted reproductive technology (ART) provide hope that the reproductive impact of cancer therapy can be reduced. Those technologies that may be applicable prior to gonadotoxic therapy are pretreatment ovarian protection with oral contraceptives or gonadotropin releasing hormone agonist; ART using pretreatment cryopreservation of embryos or gametes; posttreatment ART with donor gametes or embryos; or adoption. However, ovarian protection is not of proven benefit and oocyte/ovary cryopreservation has had only limited success to date. Information regarding cancer treatment's possible effects on fertility and ways to potentially circumvent these should be part of routine counseling to allow the patient to make an informed decision. Cancer 2006. © 2006 American Cancer Society.