The authors relate the results of examining 92 patients with acute pneumococcal pneumonia (APP). The bacteriological methods of studying the tracheal contents and pleural exudate, performed before treatment turned out highly informative. As regards the course of APP, the bacteremic , classic (infiltrative) and pleurisy-complicated varieties were distinguished. It was established that the bacteremic variety of APP may be accompanied by bactericidal shock eventuating in a lethal outcome which is not observed in other varieties. 19.6% of patients with APP demonstrated abacterial fever and 27.1% severe pleuropulmonary complications. The development of the latter ones is predictable according to the presence of pleurisy and fever lasting over 5 days. An opinion is advanced that the continuance of antibacterial therapy over 5 days is not desirable whatever the APP variety.