Heritage impact: looking for models to understand the impact of externalities

This paper aims at clarifying the relevance of the purposes that prompt the evaluations of the impact of Heritage, i.e. the set of effects produced by the set of actions concerning Heritage conservation and valorisation. The methods and the outputs will be different whether we are advocating for Heritage sector, aiming at a legitimation of the costs of heritage preservation, or we are checking the performances of policies and practices as we aim at improving them. A first requirement for the analysis of Heritage impact is to take into account the whole process of activities concerning movable and immovable heritage. In other words it is important to study Heritage game as a whole, in order to understand the mechanisms for the production of value. Alternative models can be implemented to recognize activities, phases, relationships and to highlight where and how value is born. The paper will try to show that the real alternative is to evaluate earnings and expected benefits versus acknowledge externalities. Then the most important aim of the research should be to find the way of ruling and planning Heritage Game in order to internalize externalities.