The Canadian Medical Association (CMA) maintains a database of clinical practice guidelines (CPGs) developed or endorsed by Canadian organizations. The study purpose was to describe how these guidelines were developed, disseminated and evaluated. A survey was mailed to the developer of each CPG registered in the CMA Infobase between June 1996 and December 1999. Data were received for 730 unique guidelines (response rate of 70%) developed by 75 organizations. Of these, 72% were developed by committees that had a formal process for selecting their members. The scientific literature was reviewed for all of the guidelines, a computerized search undertaken for 88% and the search strategy included 34% of CPG documents. An attempt was made to grade the quality of the evidence underpinning 54% of the guidelines. For most guidelines, consensus about values or judgements was reached by expert opinion through open discussion (78% of guidelines). The most common strategies used to disseminate the guidelines were direct mailing of guidelines to members of the developing organization (80% of all guidelines), publishing guidelines in newsletters/journals (76%), direct mailing to others (73%), electronic dissemination (62%), educational or continuing medical education activities (50%), and providing information about guidelines to patients/consumers (47%). Overall, 5% of the guidelines have been evaluated to determine their impact on health outcomes. During the 5-year study period (1994-99), the more recent guidelines were more likely to use multidisciplinary development panels, report the literature search strategies and grade the quality of the evidence. The CPG development process in Canada is becoming more rigorous and reproducible, but there is still considerable room for improvement. In addition to encouraging Canadian guideline developers to use more rigorous and transparent methods, considerably more attention must be focused on using and identifying effective and cost-effective strategies to promote and facilitate the uptake of guidelines by practitioners and to evaluate the impact of guidelines on patient outcomes.