Seven dogs, three with surgically-induced acute myocardial infarction, were subjected to the effects of static electricity discharged from our fingertips onto the external end of a transvenous right ventricular pacemaker. Initiation of ventricular beats occurred regularly when shocks were perceptible to the generating person and, not infrequently, when energy levels were below perception. In one dog with myocardial infarction, ventricular fibrillation was clearly related to the static discharge. The data obtained in this study support the recommendations of the Electrical Safety Hazard committee that critical care areas not be carpeted in order to minimize static discharges. In addition to low static floor covering in these areas, one can reduce static charge by the use of foot coverings such as those worn in the operating room. We found that no static charge could be developed when wearing the expandable operating room "booties." Since static charges were transmitted through our fingertips, probably the best means of protecting the electrically sensitive patient against the hazard of static electricity is to instruct personnel to wear rubber gloves whenever direct contact with the external ends of a pacing catheter becomes necessary. Routinely, such exteriorized pacemaker ends should also be covered with a nonconductive substance.