We investigated the guidelines in British hospitals for the management of adults admitted with community-acquired pneumonia (CAP). A questionnaire was sent to one consultant respiratory physician in each of the 263 hospitals in the British Thoracic Society (BTS) Directory of Training Posts and Services. Two hundred and thirteen (81%) responses were received: 178 (84%) had written CAP guidelines, of which 123 (69%) printed copies were received. For non-severe CAP a single antibiotic (74% of guidelines-most frequently amoxycillin or ampicillin) was the usual recommendation with the combination of a beta-lactam and a macrolide the second most frequent (24%). The latter combination was recommended for severe CAP in 81% of guidelines. Clostridium difficile-associated diarrhoea had influenced guideline recommendations, or was commented on as a concern, in 18% of responses. Written guidelines for antibiotic therapy in adults with CAP exist in most British hospitals and follow broadly the 1993 BTS guidelines, although combination therapy is used not infrequently for non-severe CAP.