It is important today to take account of the opinions of both experts and stakeholders in the sustainable management of forests. SILVANET (Universidad Politécnica de Madrid, Madrid, Spain) is a software package that offers a useful methodology for assessing the preferences of individuals or groups, and applying them to the design of a sustainable forest management plan. The program starts by identifying the personal preferences of the evaluators based on information provided individually when comparing and selecting sustainability options from a series of site pairs. The evaluator is given information on certain sustainability indicators obtained in the area to be assessed. The scope of the evaluator’s knowledge of sustainable forest management and the consistency of his/her decisions is assessed, and he/she is then included in a group of people with similar systems of preferences to encourage interaction between evaluators in the same group. The preferences are characterized by matrices that encode individual assessments, the maximization of their utility and the analysis of past decisions. Finally, by identifying preferences, we are able to design the forest management system that maximizes the concept of sustainability for each individual or group of individuals. In this paper, we present the results of its application to mono-specific conifer forest stands, although it can be adapted to other forest types. The forestry management experts classify its usability as good, although non-expert users give it a lower rating.