To assess the attitudes of practicing general internists toward evidence-based medicine (EBM-defined as the process of systematically finding, appraising, and using contemporaneous research findings as the basis for clinical decisions) and their perceived barriers to its use. Cross-sectional, self-administered mail questionnaire conducted between June and October 1997. Canada. Questionnaires were sent to all 521 physician members of the Canadian Society of Internal Medicine with Canadian mailing addresses; 296 (60%) of 495 eligible physicians responded. Exclusion of two incomplete surveys resulted in a final sample size of 294. Mean age of respondents was 46 years, 80% were male, and 52% worked in large urban medical centers. Participants reported using EBM in their clinical practice always (33, 11%), often (173, 59%), sometimes (80, 27%), or rarely/never (8, 3%). There were no significant differences in demographics, training, or practice types or locales on univariate or multivariate analyses between those who reported using EBM often or always and those who did not. Both groups reported high usage of traditional (non-EBM) information sources: clinical experience (93%), review articles (73%), the opinion of colleagues (61%), and textbooks (45%). Only a minority used EBM-related information sources such as primary research studies (45%), clinical practice guidelines (27%), or Cochrane Collaboration Reviews (5%) on a regular basis. Barriers to the use of EBM cited by respondents included lack of relevant evidence (26%), newness of the concept (25%), impracticality for use in day-to-day practice (14%), and negative impact on traditional medical skills and "the art of medicine" (11%). Less than half of respondents were confident in basic skills of EBM such as conducting a literature search (46%) or evaluating the methodology of published studies (34%). However, respondents demonstrated a high level of interest in further education about these tasks. The likelihood that physicians will incorporate EBM into their practice cannot be predicted by any demographic or practice-related factors. Even those physicians who are most enthusiastic about EBM rely more on traditional information sources than EBM-related sources. The most important barriers to increased use of EBM by practicing clinicians appear to be lack of knowledge and familiarity with the basic skills, rather than skepticism about the concept.