Objective: To report results from a national survey of coordinators and managers of clinical research studies in the US on their perceptions of and experiences with scientific misconduct. Methods: Data were collected using the Scientific Misconduct Questionnaire-Revised. Eligible responses were received from 1645 of 5302 (31%) surveys sent to members of the Association of Clinical Research Professionals and to subscribers of Research Practitioner, published by the Center for Clinical Research Practice, between February 200A and January 2005. Findings: Overall, the perceived frequency of misconduct was low. Differences were noted between workplaces with regard to perceived pressures on investigators and research coordinators, and on the effectiveness of the regulatory environment in reducing misconduct. First-hand experience with an incident of misconduct was reported by 18% of respondents. Those with first-hand knowledge of misconduct were more likely to report working in an academic medical setting, and to report that a typical research coordinator would probably do nothing if aware that a principal investigator or research staff member was involved in an incident of misconduct. Conclusion: These findings expand the knowledge on scientific misconduct by adding new information from the perspective of research coordinators. The findings provide some data supporting the influence of workplace climate on misconduct and also on the perceived effectiveness of institutional policies to reduce scientific misconduct.