Giving Voice or Quelling Dissent? The Case of the Civil Society Advocating for Climate Change through SDG 13 in Spain

International nongovernmental organizations (INGOs) play a vital, yet contested, role in responding to global challenges. Do INGOs serve to advance the interests of grassroots social movements or temper demands as they bring popular voices into institutional power settings? This study focuses on how civil society in Spain engages with the UN Sustainable Development Goal 13 on climate action and argues that INGOs simultaneously provide voice for some and temper the message of others. The seemingly contradictory impacts can be understood by examining the interplay of institutional political opportunity structures and network relations. A transcalar examination reveals that Spanish environmental INGOs work in network coalitions with domestic environmental social movements developing common positions. While limited by domestic political opportunity structures, these relations are mutually beneficial. In contrast, transnational environmental social movements do not closely coalesce with INGOs due to their loose organizational structures and lack of specific policy positions.