The gastrointestinal (GI) tract is responsible for the transport of food and absorption of nutrients. Gastrointestinal pathology is a sub-branch of surgical pathology that is concerned with the characterization and diagnosis of neoplastic and non-neoplastic diseases of the GI tract. The diagnostic evaluation of the GI tract or the biopsy pathology of GI tissue are essential for gastrointestinal pathology. Understanding of the clinical presentations of GI diseases, their diagnoses and treatment modalities, disease mechanism and histomorphology, etc. are vital elements of gastrointestinal pathology. The pathologic conditions of the gastrointestinal tract impair GI functions. The chief symptoms associated with the pathologies of the GI tract are gastrointestinal hemorrhage and abdominal pain. Acute abdominal pain can arise due to gastrointestinal inflammations (pancreatitis, appendicitis, cholecystitis and diverticulitis), gastrointestinal obstruction, perforation and vascular diseases (ruptured abdominal aortic aneurysm and acute ischemia). The diagnosis of upper gastrointestinal bleeding is possible with endoscopy, while the diagnosis of lower gastrointestinal bleeding requires colonoscopy or sigmoidoscopy. This book aims to shed light on some of the unexplored aspects of gastrointestinal pathology and the recent researches in this domain. The objective of this book is to give a general view of the different gastrointestinal diseases, and their management strategies. It is a vital tool for all researching or studying gastrointestinal pathology as it gives incredible insights into emerging trends and concepts.