Sri Lanka, though small in size, is part of a global Biodiversity Hotspot due to its rich biodiversity and increasing threats from habitat encroachment, unsustainable resource use, pollution, and invasive species. While 28% of the country is covered by Protected Areas (PAs), many critical ecosystems exist outside these zones. Recognizing this, the Ministry of Environment and UNDP, with funding from the GEF, implemented a co-management approach in Environmentally Sensitive Areas (ESAs) landscapes with high biodiversity and ecosystem service value outside formal PAs. The approach engaged public and private sectors, along with local communities, to conserve biodiversity while sustaining the ecological and socio-economic benefits essential to surrounding populations. It promoted inclusive and sustainable management practices, balancing conservation with responsible resource use, and enabling collaborative agreements between communities and the government. This approach is vital to safeguard Sri Lanka’s unique biodiversity.