Introduction: It is well documented that athletes report greater dietary supplement (DS) usage than nonathletes; however, limited data exist for Canadian athletes, especially relative to competitive performance levels. Purpose: This descriptive and analytical, cross-sectional research investigated DS practices and opinions, preferred means for DS education, and antidoping opinions among elite Canadian athletes competing at various performance levels. Methods: Subjects completed a validated questionnaire by recall. Combined, 582 high-performance athletes (314 M 268 F) between the ages of I I and 42 yr (mean 19.96 +/- 3.91 yr) and representing 27 sports activities participated. Respondents were categorized into five competitive performance levels: provincial (68). national (101). North America (61), international or professional (89). and 14 varsity (263). Results: Overall, most (88.4%) reported taking one or more DS during the previous 6 months (mean 3.08 +/- 1.87 DS per user). From a total of 1555 DS declared, sport drinks (22.4%). sport bars (14.0%), multivitamins and minerals (13.5%). protein supplements (9.0%), and vitamin C (6.4%) were most frequently reported. Athletes at the highest performance level were significantly more likely to use protein supplements, to be advised by strength trainers regarding DS usage. to have a higher self-rating of their diet, to prefer individual interviews for DS educational purposes, to perceive Mater awareness of antidoping legislation. and train more h(.)wk(-1). Furthermore, differences were observed for the types of DS reported and justifications for use. Conclusion: This dataset. the first of its kind in Canada, was generated with a validated and reliable questionnaire and has the potential to be extended nationally and internationally to provide greater insight into the patterns and opinions of elite athletes regarding supplementation and antidoping.