Wetlands generate many benefits important for our well-being. They support water-balance, maintain rich biodiversity, regulate the levels of CO2. But human activity and unsustainable management have made them vulnerable. WWF picked one protected area in Bulgaria – Persina Nature Park – to demonstrate the socio-economic value of wetlands through the principles of Payments for Ecosystem Services (PES). This new approach to nature conservation constitutes a variety of arrangements through which people who benefit from the services of nature reward those whose lands provide these services.