The problems of getting people to act on evidence based guidelines are widely recognised. 1 An overview of 41 systematic reviews found that the most promising approach was to use a variety of interventions including audit and feedback, reminders, and educational outreach. 1 The effective interventions often involved complicated procedures and were always an addition to the provision of guidelines. None of the studies used the simplest intervention—that is, changing the wording of the guidelines. We examine the importance of precise behavioural recommendations and suggest how some current guidelines could be improved.