While prior studies have shown the importance of participatory institutions in strengthening civil society and in improving policy outcomes, we know much less about why some participatory institutions take root while others do not.This book explains the divergent trajectories of nationally mandated participatory institutions' 'stickiness' by highlighting the powerful and lasting impacts of their origins in different policy-reform projects.Mayka argues that participatory institutions take root when they are bundled into sweeping policy reforms, which upend the status quo and mobilize unexpected coalitions behind participatory institution building.In contrast, participatory institutions created through reforms focused on deepening democracy are easy for entrenched interests to dismantle and sideline.Building Participatory Institutions in Latin America draws on rich case studies of participatory institutions in Brazil and Colombia across three policy areas, offering the first cross-national comparative study of participatory institutions mandated at the national level.