Best Sustainable Practices: A Comparative Study of Environmental and Developmental Strategies among Southeast Asian Countries

This study conducts a comparative analysis of sustainable development practices across the 10 ASEAN member states, addressing gaps in cross-national evaluation, transferability of best practices, and alignment with global frameworks such as the UN Sustainable Development Goals (SDGs). Using a qualitative comparative case study approach and documentary analysis (2020–2025), the research identifies key innovations in sectors including energy, tourism, and urban planning. Notable patterns include innovation-driven strategies in Vietnam and Singapore, and community-based initiatives in Thailand and Myanmar. Despite progress, sustainability implementation remains uneven due to policy fragmentation, capacity gaps, and financial disparities. A SWOT analysis and cross-case synthesis highlight shared success factors, such as stakeholder engagement and policy coherence, while proposing a flexible regional framework grounded in governance alignment, capacity building, and inclusive financing. Limitations include reliance on secondary data and lack of triangulation. The study provides actionable insights for fostering cohesive, adaptive, and equitable sustainability transitions across Southeast Asia.