Coronary catheterization laboratories (CCLs) are the cornerstones of the delivery system for many cardiovascular procedures performed in the United States. However, few comprehensive data exist benchmarking physician activities in CCLs. This study benchmarks cost and time data on 82,548 consecutive patient encounters in 53 CCLs for the 18-month period of January 1997 through June 1998. The data are compiled from the OEP program, a relational database developed by Boston Scientific/Scimed (Maple Grove, Minnesota) for use in CCLs. CCL productivity (total time and procedure time) and cost (variable costs and device costs) benchmarks are created for: 1) left heart catheterization; 2) right and left heart catheterization; 3) percutaneous transluminal coronary balloon angioplasty (PTCA); 4) atherectomy; and 5) coronary stents. Results show the variable costs (those costs that vary in direct proportion to changes in CCL activities) for the five procedures are: $308, left heart catheterization; $395, right and left heart catheterization; $841, PTCA; $2,768, atherectomy; and $3,186, coronary stent. These variable costs are lower than the typical average costs reported for these procedures because they do not include hospital, laboratory, and physician costs, only the procedure-specific activity-related costs most directly controlled and/or influenced by CCL physicians or administrators. The total time for the left heart catheterization averaged 64 minutes and 84 minutes for the right and left heart catheterization, respectively, and procedural times averaged 25 and 32 minutes, respectively. For the major interventional procedures N PTCA, atherectomy, and coronary stents, total times averages were 102, 135, and 117 minutes, respectively. Procedural times for these procedures averaged between 60 and 65 percent of the total time. The major implications of these findings are discussed and limitations noted.