Implementing clinical practice guidelines improves outcomes. This has been shown by several large scale registries. However, in spite of this, guidelines are poorly implemented in clinical practice for a wide variety of reasons. We examine the reasons behind the low uptake of guidelines into routine medical practice. Many physicians are simply not aware that guidelines exist; or they do not believe in them; or they simply do not care to implement them. Economic and social factors may also influence uptake of guidelines. It is the role of professional societies to disseminate best scientific knowledge, and ensure optimum implementation of guidelines. This can be achieved through educational activities and CME credit. Close collaboration between the profession, health authorities, and maybe even the industry could improve uptake of clinical practice guidelines, and thereby improve patient outcome.