Hepatic arterial infusion (HAI) entails the surgical implantation of a subcutaneous pump to deliver chemotherapeutic agents directly to the liver in the setting of primary or secondary liver cancer. The purpose of HAI chemotherapy is to maximize hepatic drug concentrations while minimizing systemic toxicity, facilitating more effective treatment. HAI is used in combination with systemic chemotherapy and can be considered in several clinical scenarios, including adjuvant therapy, conversion of unresectable disease to resectable disease, and unresectable disease. Radiologists are key members of the multidisciplinary team involved in the selection and management of these patients with complex liver disease. As these devices begin to be used at more sites across the country, radiologists should become familiar with the guiding principles behind pump placement, expected imaging appearances of these devices, and potential associated complications. The authors provide an overview of HAI therapy, with a focus on the key imaging findings associated with this treatment that radiologists may encounter. ©RSNA, 2021.