## 3 Sustainability as One of the Fundamentals for SEA Processes
The SEA Directive states that \"\"Environmental assessment\" shall mean the preparation of an environmental report, the carrying out of consultations, the taking into account of the environmental report and the results of the consultations in decision-making and the provision of information on the decision in accordance with Articles 4 to 9\" [15]. The concept of endogeneity is not integrated into the Italian Law enacted by decree 2006/152, which implements the SEA Directive into Italian legislation. This law establishes that \"The SEA authority and the Planning authority implement the technical development of the SEA process, collect and assess all the available documents, that is observations, objections and suggestions coming from the public [...] express their motivated statement within ninety days from the deadlines established by art. 14\" [16]. So, in Italian legislation, SEA and planning processes are separated, which could cause a substantial failure of the SEA process. In other words, it is very possible that environmental protection- and sustainability-based priorities coming from the SEA will not be considered as apart of the strategic priorities of a (city Master) plan [17]. From this point of view, SEA is a participatory, cooperative and incremental process, which aims at continuously improving the quality and effectiveness of a (city Master) plan. So, a motivated statement issued by a SEA authority who did not take part in the decision-making process of a plan, whose statement would be entirely analogous to the compatibility statement which concludes the Environmental Impact Assessment process of a project, should not be the desirable end of a SEA process. An adequate SEA process should rather be characterized by the active participation of each public administration sector involved, all of which should share their opinions, project objectives, procedures and policies concerning the future local economic and social development. The SEA endogenous process is cooperative and inclusive _ad intra_ in that its stakeholders belong to public administration, but, at the same time, it should entail the implementation of an analogous implementation _ad extra_, that is one which involves the local communities. So, the most important ontological characteristics of SEA are cooperation between SEA and planning public authorities, and participation and inclusion of the private stakeholders in the assessment of plans [18]. The endogenous and participatory/inclusive SEA process should imply continuous feedback on the implementation status of planning policies. In this process, all of the participants should improve their knowledge of the plan, its environmental impacts, and how its policies address the territorial issue at stake. The public and private participants' cooperative attitudes should improve through the SEA as well [19]. Increased social learning, both in qualitative and quantitative terms, is one of the most important outcomes of endogeneity and participation/inclusion. The three fundamentals of the ontology of SEA processes concerning city Masterplans should entail analysis and interpretation of the environmental and territorial domains of the plans. Analysis and interpretation should effectively represent the domains through concepts and relations, making reference to international, national and local legislative frameworks. In the following section, we tentatively propose an ontology having these features.