The significance of polymer-associated infections caused by coagulase-negative staphylococci is discussed. The aspects of bacterial adhesion to polymeric materials as the first important pathogenetic step in the development of such infections are treated. The role of extracellular slime substance (ESS) produced by the bacteria in the pathogenesis is elucidated und newer results concerning the interference of ESS with host defense mechanisms and antibiotic therapy lire presented. As an approach to the prevention of the prevention materials is infections. the modification of the polymeric materials is introduced. Results of recent studies to achieve materials by radiation modification of polymers as well as the development of antimicrobial surfaces by incorporating or bonding antibiotics to polymers are presented.