The authors conducted a Safety Attitudes Questionnaire (SAQ) in eight hospitals participating in a trial of a WHO surgical safety checklist. Clinicians (n=281) in the preintervention phase had a mean SAQ score of 3.91 (1-5 scale where 5 represents better safety attitude) while the postintervention group (n=257) had a statistically significantlly different mean of 4.01. Improvements in postoperative outcomes were associated with improved perception of teamwork and safety climate among respondents, suggesting that changes in these may be partially responsible for the effect of the checklist. Clinicians held the checklist in high regard and 93.4% would want it used if they were undergoing surgery themselves.