Background: Since endoscopic retrograde cholangiopancreatography (ERCP) introduction in 1968, it has been an essential endoscopic technique for the diagnosis and treatment of pancreato-biliary diseases. ERCP is an advanced endoscopic technique that is challenging for trainees for several reasons such as the use of side view endoscope, procedural complexity, and risk of complications. As a result, proficiency in using an upper gastrointestinal endoscope is imperative and a precise understanding of the pancreato biliary anatomy and physiology is essential. When selective biliary cannulation (SBC) using the techniques described is not easily achieved, it is considered a difficult cannulation. Over the years, there have been several attempts to objectively define difficult cannulation. Most definitions use a combination of a minimum number of cannulation attempts, typically 5 to 15, and a minimum time spent on standard cannulation techniques, typically greater than 5 to 20 min. The concept of difficult biliary cannulation (DBC) has changed over time (3-5). Recently, the European Society of Gastrointestinal Endoscopy (ESGE) redefined DBC as more than five contacts with the papilla, unsuccessful cannulation longer than 5 minutes, or more than one unintentional cannulation or opacification of the pancreatic duct (PD).