Primary care clinicians initiate and oversee colorectal screening for their patients, but colonoscopy, a central component of screening programs, is usually performed by consultants. The accuracy and safety of colonoscopy varies among endoscopists, even those with mainstream training and certification. Therefore, it is a primary care responsibility to choose the best available colonoscopy services. A working group of the National Colorectal Cancer Roundtable identified a set of indicators that primary care clinicians can use to assess the quality of colonoscopy services. Quality measures are of actual performance, not training, specialty, or experience alone. The main elements of quality are a complete report, technical competence, and a safe setting for the procedure. We provide explicit criteria that primary care physicians can use when choosing a colonoscopist. Information on quality indicators will be increasingly available with quality improvement efforts within the colonoscopy community and growth in the use of electronic medical records.