Section I: Oesophageal Biopsy. Normal Appearances in Oesophageal Biopsy Specimens. Gastro-Oesophageal Reflux and Oesophagitis, Barrett's Oesophagus and Ectopic Gastric Mucosa. Nonreflux Oesophagitis and Ulceration. Oesophageal Plaques and Miscellaneous Conditions. Section II: Gastric Biopsy. Normal Appearances in Gastric Biopsy Specimens. Gastritis. The Classification of Chronic Gastritis: Current Status. Gastric Epithelial Dysplasia and Early Gastric Cancer, Mucosal Hyperplasia, Epithelial Polyps and Polyposis, Lymphoid Hyperplasia and Malignant Lymphoma. Other Types of Gastritis and Miscellaneous Lesions. Section III: Small Intestine Biopsy. Normal Appearances in Small Intestine Biopsy Specimens. Small Intestine Biopsy in Disease. Lymphoma in Coeliac Disease, Unresponsive, Collagenous and Ulcerative Coeliac Disease, Mediterranean Lymphoma. Parasitic Diseases. Miscellaneous Conditions. Section IV: Colonic Biopsy. Normal Appearances in Colonic Biopsy Specimens. Ulcerative Colitis, Crohn's Colitis, Ischaemic Colitis, Pseudomembranous Colitis, And Antibiotic-Associated Colitis. Other Forms of Colitis. Miscellaneous Lesions. Section V: Human Immunodeficiency Virus Infection and Mucosal Biopsy. Acquired Immunodeficiency Syndrome. Oesophageal and Gastrointestinal Manifestations.