Anaerobes are the predominant components of the bacterial flora of normal human skin and mucous membranes, and are therefore a common cause of bacterial infections of endogenous origin. Infections due to anaerobic bacteria can evolve all body systems and sites . The predominant ones include: abdominal, pelvic, respiratory, and skin and soft tissues infections. Because of their fastidious nature, they are difficult to isolate from infectious sites and are often overlooked. Failure to direct therapy against these organisms often leads to clinical failures. Their isolation requires appropriate methods of collection, transportation, and cultivation of specimens. Treatment of anaerobic bacterial infection is complicated by the slow growth of these organisms, which makes diagnosis in the laboratory possible only after several days, by their often polymicrobial nature and by the growing resistance of anaerobic bacteria to antimicrobial agent.