Paper Title
Catalonia 2026: A Study about the Internalization of Externalities

Abstract
This paper presents a brief theoretical study on the theme internalization of externalities belonging to axis four of the Strategy for the Sustainable Development of Catalonia, horizon 2026. This paper is justified due to the relevance that thematic of sustainability gains day after day making the analysis of the Catalan initiative useful both as feedback to implementers and implementers of the action plan and to society at large. Some concepts related to the subject of study are approached and its conjuncture with the Catalan contemporaneity is commented. Keywords - Sustainable development, Catalonia, Externalities, Economics.