This work tries to contribute to closing the existing gap in the relationship between sustainability and smartness, patent both in the field of research and in the management of cities and tourist destinations. The points in common between the concepts of sustainability and smartness applied to the management of tourist destinations are analyzed, as well as the critical factors that hinder its practical application, as a starting point to move towards a synergistic model for sustainable tourism destinations, called Smart Sustainability. This proposal is based on a true governance of the destination and is aimed at taking advantage of the opportunities offered by information and communication technologies (ICTs) for a more efficient and sustainable management.