Support for Institutional Animal Care and Use Committees (IACUCs) varies among those in animal use-related professions. The authors designed and carried out an anonymous survey to solicit opinions on the structure and organizational functions of IACUCs. They found that most respondents believed a single, institution-based IACUC was an appropriate venue for institutional approval of animal care and use, that their IACUCs represented their institutions' constituencies and that the unaffiliated IACUC members adequately represented their surrounding communities. Respondents believed that members came prepared for IACUC meetings, and a majority agreed that full committee reviews were more thorough than designated member reviews. The quality of veterinary care for animals was deemed to be very good. Participants reported that the status of the person submitting an animal use protocol, the perceived monetary value of a grant associated with a protocol and pressure for a rapid protocol review did not alter the quality of the protocol review. On many of the survey items, opinions of IACUC members differently significantly from those of non-members, and opinions of non-member IACUC administrators differed from those of IACUC chairpersons, perhaps owing to differences in responsibilities and perceived status.