Cholangiocarcinoma, the second most common hepatobiliary malignancy after hepatocellular carcinoma, is a heterogeneous disease entity with widely varying radiologic features, clinical behavior, and treatment approaches. In the detection, characterization, staging, and resectability assessment of cholangiocarcinoma, imaging studies are indispensable. Herein, an overview of the state-of-the-art imaging techniques is presented for the evaluation of intrahepatic and perihilar cholangiocarcinoma, as well as complementary multimodality and multiparametric imaging approaches for a more comprehensive evaluation. In addition, classification systems, new pathologic concepts in cholangiocarcinogenesis and premalignant lesions, and current trends in treatment approaches, which are vital to the imaging interpretation of cholangiocarcinoma, will be discussed. © RSNA, 2018.