The Danube River Network of Protected Areas (Slovakia – Austria – Bulgaria – Croatia – Germany – Hungary – Romania – Hungary – Serbia – Ukraine)
Carpathian wetlands Initiative to ensure and support the effective conservation and wise use of wetlands in the Carpathian region (Slovakia – Czech Republic – Hungary – Poland – Romania – Serbia – Ukraine)
Shared protected areas between neighboring states (Slovakia – Austria – Czech Republic – Poland – Ukraine)
Bilateral Commissions and Institutions Cooperation in nature and landscape protection (Slovakia – Hungary – Poland – Ukraine)
Need to overcome legal issues, territorial, organizational and administrative procedures (Portugal – Spain)