The digestive system comprises everything from the mouth to the anus, and includes the liver, biliary tree, gallbladder and pancreas. It can give rise to a huge number of medical (and psychological) conditions, which in turn manifest themselves as disturbance in gut functioning and a variety of symptoms with a wide differential diagnosis. In this chapter we’ll focus on what to ask when faced with abdominal pain, eructation and the like. The key condition that Gastroenterologists are arguably most interested in is bowel cancer as it remains a significant source of morbidity and mortality.