Indeterminate biliary strictures refer to biliary strictures without an identifiable cause on imaging. The endoscopist's role is to determine if the stricture is benign or malignant and offer treatment options. Available tools for evaluation include ERCP, cholangioscopy, intraductal ultrasound (IDUS), and endoscopic ultrasound (EUS). ERCP allows for tissue sampling but has limited sensitivity. Newer techniques like fluorescence in-situ hybridization and confocal endomicroscopy show promise to improve detection. Direct visualization with cholangioscopy may also improve detection over standard techniques. IDUS provides diagnostic accuracy without direct sampling. EUS allows for tissue acquisition with fine needle aspiration and evaluation of local