Using the discrete choice experiment (DCE) approach, this study estimates the public preferences for a public policy with the primary goal of protecting the environment. The policy under investigation is a ban issued by the Italian region of Sardinia that aimed to preserve the island’s land, landscape and coastal environment. Two waves of surveys were undertaken with separate random samples in 2006 and 2010, which allowed for operationally capturing and estimating the temporal stability of welfare measures regarding the environmental public policy. Overall, the results suggest that the preferences for the environmental protection are not stable over time, and signal increasing public concern for future generations and the satisfaction derived from preserving the natural environment. This study brings to light the importance of truly understanding and monitoring over time how citizens perceive the potential impacts of environmental and land development policies.