This colour guide to clinical signs is aimed primarily at undergraduates, but can also be used as a revision aid for postgraduate surgical examinations. The emphasis is on common conditions, but rarer diseases which present with classic clinical features are included. Some common and important conditions produce few specific signs which are difficult to photograph, and depend on special investigation for diagnosis, such as upper gastrointestinal cancer and pancreatitis. There are scans and radiographs for some of these, while others, such as oesophageal carcinoma, have been purposely omitted.