Diagnostic and therapeutic cardiac catheterization procedures bypass natural host defenses and thereby pose a risk of infection. Early-onset infections resulting from these procedures can be related to bacterial entry into the host via the bloodstream. Therefore, sterile technique for vascular access is very important for all vascular access procedures. Especially worrisome are the late-onset infections that can occur with implantable devices (e.g., pacemakers, stents). Patient preparation and sterile technique are key strategies to reduce the risk of infection associated with these devices.