Benchmarking is generally considered to be an important tool for quality improvement. Traditional approaches to benchmarking have relied on subjective identification of 'leaders in the field'. We derive an objective, reproducible and attainable Achievable Benchmark of Care (ABC) by measuring and analysing performance on process-of-care indicators. Three characteristics of the ABC that we deem essential are: (1) benchmarks represent a measurable level of excellence; (2) benchmarks are demonstrably attainable; (3) benchmarks are derived from data in an objective, reproducible and predetermined fashion. From these characteristics it follows that (4) providers with high performance are selected to define a level of excellence in a predetermined fashion, but (5) providers with high performance on small numbers of cases do not influence unduly benchmark levels. We use the 'pared mean' to operationalize the ABC. Roughly, the pared mean summarizes the performance of top-ranked providers whereby at least 10% of the patient pool across all providers is included. Bayesian estimators for adjustment of performance of providers with small sample sizes are used to rank providers. Randomized controlled trials to assess the independent effect of the ABC in quality improvement projects are under way. We have developed a methodology objectively and reproducibly to derive a level of excellent, attainable performance, based on measured performance by a group of providers. The ABC can be applied to groups of providers in communities, to institutions and departments within them, or to individual practitioners.