Green theory in International Relations emphasizes environmental issues and sustainability, challenging traditional approaches that neglect ecological concerns. It argues that environmental degradation and resource scarcity are major sources of global conflict and insecurity, calling for a fundamental rethinking of human-nature relationships. Key thinkers like Arne Naess, Vandana Shiva, and Murray Bookchin have shaped green theory's development. The approach advocates for global cooperation, collective action on environmental challenges, and integrating ecological principles into international relations. It highlights the interconnectedness of social, economic, and ecological systems.