In-transit metastasis (ITM) develop in approximately 1 in 10 patients with melanoma and the disease course can vary widely. Surgical resection is the gold-standard treatment; however, ITM are often surgically unresectable due to size, distribution, and/or anatomic involvement. Oncolytic viral therapies are one category of non-surgical treatment options available for ITM. They induce tumor cell lysis and systemic anti-tumor activity through selective infection of tumor cells by naturally occurring or genetically modified factors. While there are numerous oncolytic viral therapies in various stages of development for the treatment of ITM, this discussion focuses on the mechanism and available literature for the two most established herpes virus-based therapies.