A steadily increasing number of research trials and prevention advocates are identifying the practice environment as the main source of both problems and solutions to the improved delivery of clinical preventive services. Although these sources are correctly focusing on office systems as solutions, there is a tendency to focus on only parts of a system and to relate this to just one or a few related preventive services. However, the effort required to set up and maintain an office system makes it difficult to justify doing so for a single clinical activity. The process and system thinking of Continuous Quality Improvement (CQI) theory suggests that there may be both efficiency and effectiveness advantages to the concept of all clinical preventive services being served by a single system with many interrelated component processes. Such a system should be usable for all age groups. This system and its literature base are described. The feasibility of applying this concept is being tested in a randomized controlled trial in 44 primary care clinics in Minnesota and Wisconsin.