Other Effective Area-Based Conservation Measures (OECMs) in Global Area-Based Conservation

Other Effective Area-Based Conservation Measures (OECMs) are an emerging area-based conservation mechanism aspiring to achieve long-term and effective in situ biodiversity conservation outside traditional protected areas. Contributing toward several global biodiversity targets, they combine protection with sustainable land use and human development. This review analyzes spatial and temporal trends in OECM site designation (2010–2024), exploring governance frameworks, management, and ecological effectiveness in reducing biodiversity loss, addressing environmental change, and promoting sustainable development. Emphasis is placed on inclusivity of OECMs, particularly engagement of local communities and Indigenous Peoples in stewardship and decision-making, thereby enhancing social equity and cultural relevance. Academic and policy attention has centered on two areas: (a) refining the OECM framework, its definition, characteristics, and alignment with international goals (Section 3), and (b) evaluating governance, effectiveness, and national/subnational implementation (Section 4). While OECMs offer potential to expand global conservation, issues around governance and site-level outcomes remain underexplored and warrant attention (Section 5).