In economics, since many leading economists' theorists - Herbert Simon, Kenneth Arrow, Amartaya Sen, and others - have pointed out the paradoxes of rationality, the possibility of market failure, the need for a welfare economics dealing with group benefits, and the limits of economic man, Chicago school theorists do not represent the discipline of economics as a whole. And even among economists who share many of the assumptions of the Chicago school there are major controversies and differences of opinion, such as whether one can assume that rational choosers have perfect information or whether individuals who make decision do so within hierarchies and institutions. Gary Becker, for example, allows room for the other social sciences, including sociology- but only if they accept the terrain established by economics. Does this "expanding domain of economics" reflect the efforts of the Chicago school to colonize the other social sciences or/and a permanent shift in the hegemony of the social sciences by using the technique of economics? As from the perspective of the Chicago school, there is no behaviour that is not interpretable as economic, however, altruistic, emotional, disinterested, and compassionate, it may seem to others. This article could contribute to that trend without its will, as our aim is to stress out that psychological behaviour matters in economics and from there, it can be found some economics value and returns at working on psychological variables. If emotional or compassionate behaviour can find an explanation in an economic approach, in the upside down, emotional behaviour has to be taken into account in economic theory as it can have major returns and impacts in economics. I will argument this position in the perspective of an optimal constitution and exploitation of Human Capital through a conceptual framework that I named "Emotional Capital". In my presentation, I will discuss the assertion in the perspective of an optimal constitution and exploitation of Human Capital, through a conceptual framework that I named "Emotional Capital" (EC). Referring to emotional intelligence, I will show that emotional capital, more than an additional capital, is a booster capital potentializing or energyzing the human, social and cultural capitals. EC is critical to enable human capital formation, accumulation and, its optimal exploitation for individuals and crucial in knowledge management in the today's increasingly complex and competitive global workplace for companies and organisations. This conceptual model enables to understand student academic success or failure on the one hand, the different occupational and jobs choices and career prospect between men and women, and organisations or companies successes as well, on the other hand.Author ReferencesGendron B. (2004), Why Emotional Capital Matters in Education and in Labour? Toward an Optimal Exploitation of Human Capital and Knowledge Management, in Les Cahiers de la Maison des Sciences Economiques, série rouge, n 113, Paris: Université Panthéon-Sorbonne, 35 p.Gendron B. (2004c), Emotions and Learning, and Success: Which links? The Emotional Capital, A case study on students at the Vocational School Leaving Certificate Level in France, European Conference on Educational Research 2004, September, Crete, Greece: University of Rethymno.Gendron B. (2004a), La " raison " des émotions ? Une analyse de l'évolution des représentations sociales des filières de baccalauréat professionnel, Congrès International AECSE 2004, Paris : Cnam.Gendron B. (2002a), " Management, compétences et qualité en éducation : innovations pédagogiques en formation professionnelle, le cas des baccalauréats professionnels en France ", International Conference, ADMEE, University of Lausanne, September, Switzerland.