Clinical practice guidelines are one of the foundations of efforts to improve health care. In1999, we authored a paper about methods to develop guidelines. Since it was published, themethods of guideline development have progressed both in terms of methods and necessaryprocedures and the context for guideline development has changed with the emergence ofguideline clearing houses and large scale guideline production organisations (such as the UKNational Institute for Health and Clinical Excellence). It therefore seems timely to, in a seriesof three articles, update and extend our earlier paper. In this third paper we discuss the issuesof: reviewing, reporting, and publishing guidelines; updating guidelines; and the twoemerging issues of enhancing guideline implementability and how guideline developersshould approach dealing with the issue of patients who will be the subject of guidelineshaving co-morbid conditions.