Patients with breast cancer receiving antiestrogen therapy, specifically aromatase inhibitors, often suffer from vaginal dryness, itching, irritation, dyspareunia, and dysuria, collectively known as genitourinary syndrome of menopause (GSM). GSM can decrease quality of life and is undertreated by oncologists because of fear of cancer recurrence, specifically when considering treatment with vaginal estrogen therapy because of unknown levels of systemic absorption of estradiol. In this article, we review the available literature for treatment of GSM in patients with breast cancer and survivors, including nonhormonal, vaginal hormonal, and systemic hormonal therapy options. First-line treatment includes nonhormonal therapy with vaginal moisturizers, lubricants, and gels. Although initial studies showed significant improvement in symptoms, the US Food and Drug Administration recently issued a warning against CO laser therapy for treatment of GSM until additional studies are conducted. In severe or refractory GSM, after discussing risks and benefits of vaginal hormonal therapy, the low-dose 10-μg estradiol-releasing intravaginal tablet or lower-dose 4 μg estrogen vaginal insert and intravaginal dehydroepiandrosterone (prasterone) are options for treatment, because studies show minimal elevation in serum estradiol levels and significant improvement in symptoms. The decision to offer vaginal estrogen therapy must be individualized and made jointly with the patient and her oncologist.