This paper evaluates the economic and environmental impacts of four types of policy changes that aim to enhance sustainability of upland farming. The policies assessed are either local, national or a coordinated national and local effort. Using an optimization-simulation model, the authors assess and compare policies that (1) change land use by placing local restrictions on vegetable growing, (2) require soil conservation measures to be installed and provide lump subsidy payment (local policy), (3) place a national 20 % tax on vegetable production, and (4) incorporate national and local levels, using the tax revenue to subsidize soil conservation structures.