In this study, the possibility of transforming the current status of tourism in the Balearic Islands (a region in Spain which has been under an enormous environmental pressure from conventional and massive tourism) to a sustainable tourism model is explored. Firstly, a general methodology for the conversion from standard to sustainable tourism is presented. The methodology consists of an initial audit, the selection of objectives and solutions proposed, the application of the selected solutions, an economical evaluation and a review of the obtained results. This methodology is then applied to the conversion of a real case study (“Sa Cova”) and a complete evaluation of the transformation to sustainable tourism is presented, showing an important reduction in the environmental impacts associated with tourism development (especially in areas such as energy consumption, water and waste management). The results presented here can serve as an example for the application of sustainable tourism plans to other similar regions in Spain or other traditional tourist destinations with similar problems.