Infective endocarditis remains even today a potential lethal disease. The most frequent bacterial agents are viridans streptococci, staphylococci and enterococci. Left-sided endocarditis predominates except for patients with drug addiction. Modern recommendations of treatment are based on in vitro studies, experimental data from the animal model and clinical studies. Antimicrobial therapy should be parenteral and bactericidal in character. Detailed recommendations for treatment are given. Progressive heart failure, persistent bacteremia and repeated embolism are the most important reasons for surgical intervention. Modern prevention is performed as single or short-term prophylaxis for about sixteen hours. Simple practicability as well as handing out of guidelines to the patient will contribute to improved acceptance.