Interventional oncology (IO) is a rapidly growing field in veterinary medicine and has been accepted as a fourth pillar of treatment of neoplastic disease with other modalities including surgery, chemotherapy, and radiation therapy. The major categories of IO therapies in companion animals are focused on the use of locoregional therapies and stenting of malignant obstructions. Although significant assessment of veterinary IO techniques is still necessary, early evaluation of these varying techniques is demonstrating promising results.