Theory suggests that values are important in determining an individual's behaviour and preferences related to environmental issues; however robust models that attempt to describe empirical relationships have proven elusive. This paper describes a model that clarified some relationships between values and preferences for the future management of natural areas. The key element in the model was the use of a new scale, the Natural Area Value Scale (NAVS) for measuring the relative strengths of individuals' intrinsic, non-use, use and recreation values for natural areas. Also of importance was a variable that grouped people according to their common values. The data were obtained from samples of the general public, environmentalists and farmers in Australia and were analysed in a structural equation model. The model indicated the relative importance of particular value components in determining nature conservation preferences, as well as individuals' willingness to make personal sacrifices to secure these preferences for protecting natural areas. The model fit differed for the three samples: it provided a good fit for the general public sample, for which it was designed, and weaker fit for environmentalists and farmers. The work contributes to understanding of the values that underlie conservation decisions and provides a basis for further research to develop the model's explanatory power.