Objective. To revise the existing South African community-acquired pneumonia guideline in the light of the following factors: Increased incidence of HIV. infection in South Africa e Emerging antibiotic resistance Introduction of new antibiotics International trends based on evidence published since the previous guideline. The main aim of the guideline. is to recommend an initial choice of antibiotics in patients with community-acquired pneumonia encompassing the following subgroups: (i) adults without co-morbid illness; (ii) the elderly and/or those with associated co-morbid illness, including patients with concomitant human immunodeficiency virus (HIV) infection; and (iii) patients with severe pneumonia. Options. Studies comparing patient outcome obtained with the various treatment regimens have been reviewed: The choice of antibiotic is based on the most commonly isolated pathogens, with cost as a consideration. Outcomes. The empiric antibiotic therapy covers all commonly encountered organisms in patients with community-acquired pneumonia and is likely to achieve the best prognosis. Evidence. Working group of clinicians and clinical microbiologists, following detailed literature review, particularly of studies performed in South Africa. Benefits, harms and costs. The guideline pays particular attention to cost-effectiveness in South Africa and promotes rational antibiotic prescribing with the aim of limiting emergence of antibiotic resistance. Recommendations. These include details of likely pathogens, an appropriate diagnostic approach, indicators of severity of illness, need, for hospitalisation and antibiotic treatment options. Validation. The-guideline was updated by a working group of the South African Thoracic Society, which included members of the Antibiotic Surveillance Forum of South Africa; Reference was made to the recently updated. international guidelines from the UK, Canada and the USA. Endorsement. The South African Medical Association endorsed the guideline. Guideline sponsor. The meeting of the Working Group of the South African Thoracic Society was sponsored by an unrestricted educational grant from Bayer (Ply) Ltd, Healthcare Division.