2026 will be marked by environmental sustainability resistance — and a counterbalance with activism rising in response. Companies that treat environmental sustainability programs as public relations or marketing exercises will be increasingly exposed as they back away from bold promises made just a few short years ago. But programs that are rooted in long-term vision and can show ROI will boost their companies’ investor confidence, regulatory standing, and competitive relevance. This report details Forrester’s predictions for environmental sustainability in 2026.