Conservation policies intended to address biodiversity loss and climate change are increasingly linked to land dispossession, human rights violations, and the criminalization of environmental defenders. While prior research has highlighted the risks defenders face, less is known about the strategies and conditions that enable them to succeed. This study uses crisp-set Qualitative Comparative Analysis (csQCA) of 25 conservation conflict cases from the Environmental Justice Atlas to identify the pathways through which defenders effectively resist unjust conservation practices. We identify four causal pathways to successful mobilization: two epistemic strategies, where defenders use alternative knowledge mobilization to either strengthen legal claims or build broad coalitions; one preventive strategy focused on early mobilization; and a comprehensive strategy drawing on nearly all conditions, except direct action. Across all pathways, alternative knowledge mobilization, such as defender-led health studies and ecological assessments, plays a central role in successful mobilization, while direct action tactics were notably absent in all successful pathways. These findings challenge assumptions about confrontation as a necessary ingredient for effective resistance and advance new insights into how knowledge politics shape just outcomes in conservation conflicts. As the global conservation community intensifies efforts to safeguard biodiversity and uphold the rights of affected communities, centering the strategies and experiences of environmental defenders is essential to ensuring equitable and effective conservation.