The Asthma Opinion Survey, a 33-item Likert-type instrument, was designed to measure attitudes relevant to self-management in adult outpatients. Items fall into eleven clusters; General Vulnerability, Specific Vulnerability, Attitudes Toward Patient Knowledge, Recognition of Airway Obstruction, Accessibility of Health Care, Panic-Fear, Belief in Treatment Efficacy, Staff-Patient Relationships, Sense of Control, Personal Impact, and Social Impact. Factor analysis of the clusters yielded three factors Vulnerability, Perceived Quality of Care and Recognition and Control. The items, clusters, and factors all had adequate to good score spreads and internal consistencies. Asthma opinions covaried significantly with demographic characteristics, asthma severity, and intensity of health care utilization, and correlated with the Asthma Symptoms Checklist, an instrument developed at the National Jewish Hospital-National Asthma Center, in ways supporting construct validity. These results suggest the Asthma Opinion Survey is achieving its intended purpose. © 1989 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.