This review covers the past year's literature on diagnostic studies, beginning with a discussion on the clinical usefulness of measuring intestinal permeability. The role of hydrogen breath tests and bacterial overgrowth is discussed. Some recent studies on small-bowel biopsy are mentioned. Diagnostic procedures for celiac disease and the measurement of bile salt excretion are reviewed, as well as new developments in differentiating between pancreatic and mucosal malabsorption. Small-bowel transit in anorexia nervosa is examined. Radiologic procedures are outlined, and recent findings on endoscopy are discussed.