The present paper proposes and implements an integrated evaluation framework for selecting the most appropriate sites for wind-farm development projects. This framework focuses on the combined use of geographic information systems (GIS) and spatial multi-criteria decision analysis, aiming to provide a decision tool for wind-farm planning at the regional level. This procedure has been developed by means of various technological, economic, social, and environmental criteria (known as siting criteria), which were used either as constraints and/or as evaluation factors in order to identify first the potential/appropriate sites for wind farm installation and then to evaluate these sites using a composite Suitability Index (SI). The proposed decision tool is thus able to get the optimal locations for future projects, as well as the suitability score of the already licensed projects. The results of this paper support the potential role of planners in designating areas for wind farm development.