Focusing on the concepts of scanning (gathering information about segments of the public, their reactions to the organization, and their opinions about issues important to the organization), decision making, and roles, a study examined the relationship between environmental scanning and the participation of public relations practitioners in management decision making. The 1985 membership directories for the Public Relations Society of America and the International Association of Business Communicators formed the sample frame and a questionnaire was mailed to 400 members, with a 34.8% response rate. Factor scales for environmental scanning indicated how frequently the practitioner engaged in each environmental scanning activity. An index for participation in management decision making outlined the variables and the hypotheses tested. Findings showed that both scientific and informal scanning were positively and significantly correlated with the practitioner's managerial role activities, while neither type of scanning was correlated with the practitioner's technical role activities. Some correlation existed between the technical role scale and scientific scanning. Data showed the relationship between scientific and informal scanning and management decision making to be strong, even after the influence of managerial role playing by the practitioner was controlled. (Rival models for scanning, roles, and decision making are discussed, and tables of data are included.) (JD)