The successful management of severe pneumonia involves a logical approach to antibiotic therapy, based on selecting drugs active against the most likely pathogen in each individual case while awaiting possible identification of an organism. In patients who deteriorate, more invasive diagnostic procedures should be considered in combination with broader-spectrum antibiotic treatment. Controlled oxygen therapy monitored by arterial blood-gas tension measurements is essential and mechanical ventilation may be indicated in some cases. Other measures including physiotherapy, fluid replacement, and the relief of pleuritic pain should not be forgotten.