International investment agreements (IIAs) give conflicts between mining companies and communities a transnational dimension, allowing investors to sue a state before an IIA tribunal. While investor-state disputes related to extractive industries arise from a wide range of state actions, an important subset are triggered by domestic conflicts between anti-mining groups and foreign companies. How does arbitration affect anti-mining movements? I argue that IIAs limit the government’s responsiveness to domestic pressure, reducing the ability of domestic nonstate actors to influence policies governing the extractive industry. However, it cannot be assumed that states would support these groups even without investor pressure; IIAs only have this effect when anti-mining groups are able to change the state’s preference toward the investment.