Policy backlash occurs when people or organizations mobilize against a policy during or after its enactment, diminishing the power of supporters and reducing the likelihood of the policy’s subsequent entrenchment and expansion. This article analyzes backlash as a case of negative policy feedback and explores some of the mechanisms through which backlash occurs among elites, organized groups, and mass publics. The main focus is on the politics of “backlash prevention”: using strategies to minimize the prospects of countercoalitions against policies serving diffuse or marginalized constituencies in an era of partisan polarization. These strategies include increasing the progressivity of programs after they have become embedded, recognizing that reforms can threaten the social identities and status of constituencies, and increasing reliance on low-visibility taxes. While countercoalitions cannot be completely neutralized in today’s contentious political environment, these strategies can load the dice in favor of sustainable change.