Community-acquired pneumonia (CAP) is defined as the acute infection of the pulmonary parenchyma in a patient who has acquired the infection in the community. CAP is an important cause of mortality and morbidity worldwide. While microaspiration is the most common mechanism through which pathogens reach the lung, hematogenous spread from a distant infected site, direct spread from a contiguous focus, and macroaspiration are other mechanisms. Therapy is generally begun on an empiric basis since the causative organism is not identified in as many as 50% of the cases. In this article, suggestions about diagnosis and therapy of community-acquired pneumonia are presented in the light of current literature.