Agenda-setting hypotheses inform research on both media influence and policy making. The study draws from these two literatures, building a more accurate and comprehensive model of the expanded agenda-setting process. Evidence is derived from a longitudinal dataset, including a content analysis of Canadian newspapers, results from public opinion polls, and measures of attention to issues in Question Period, committees, Throne Speeches, and legislative initiatives from 1985 to 1995. A model is estimated that accommodates dynamic, multi-directional effects. Findings are presented for three issues-inflation, environment, and debt/deficit-with an eye on examining different agenda-setting dynamics, and the degree to which these dynamics are linked to issue attributes. The results (i) demonstrate the value of an agenda-setting framework and a means of modelling media effects and the policy making process, and (2) indicate the importance of taking issue attributes into account in predicting or accounting for agenda-setting effects.