This article examines two large-scale public communication campaigns to explore the appropriateness and effectiveness of using one-way communication in contentious environmental issues. The findings show while one-way communication can be successfully employed in contentious issues, it is not appropriate for all contexts and may contribute to tensions between stakeholders. It concludes that agencies engaging in large-scale public communication campaigns involving complex and contentious environmental issues must understand the contexts in which they operate before determining their communication approach so affected communities can be both informed and engaged.