For years, the American College of Cardiology and the American Heart Association, along with other professional organizations, have produced clinical practice guidelines to improve the quality of cardiovascular care. Producing these comprehensive documents has required extraordinary effort, primarily from volunteer professionals. Quality improvement efforts based on these guidelines, however, have not fully engaged practicing physicians, as evidenced by studies of guideline adherence. The translation of the guidelines into routine practice remains a persistent challenge.Practitioners work in a complex and fast paced environment. In the routine of everyday practice, physicians, like all decision-makers, use cognitive shortcuts to help make rapid decisions under conditions of uncertainty. How practicing physicians package information in their working memory and use shortcuts called "heuristics" has implications for how clinical practice guidelines can most directly influence practice. Current guidelines are written as comprehensive review documents, but are not formatted to allow easy incorporation into the heuristics of everyday practice. Improving the interface between guidelines and routine practice may result in more rapid and appropriate translation of scientific evidence into practice.We describe the routine of everyday practice as a repetitive cycle where new scientific evidence is incorporated into the heuristics that drive daily medical decisions. Examining this cycle suggests ways to communicate guideline information more effectively and to improve practice routines. Recognizing the intuitive approaches that practicing physicians use to make rapid decisions may yield opportunities for responsive professional organizations and reflective practicing physicians to improve the quality of care.