<Tese de Doutoramento> em <Psicologia Organizational>, apresentada ao Instituto Superior de Psicologia Aplicada, sob a orientação do Prof(ª). Dr(a). <Miguel Pina e Cunha>

ABSTRACTThe work reported in this thesis addresses the research question of when and howpositive psychological states impact positive behavior and positive organizationaldevelopment. We present two theoretical essays and three empirical studies to findpossible answers to this question and we use a multitude of methodologies withdifferent epistemological assumptions, including quantitative correlation analysis, socialnetwork analysis and qualitative grounded theory analysis. In the whole, our workshows that positive psychological states are fundamental to promote individual andorganizational higher-levels of performance and well-being. It also points that thecapability to induce positive psychological states in others (an ?alter-positive?approach) is a powerful way to develop outstanding individuals and organizations. In abroader sense, it stresses the need to promote good vibrations as a fundamental route tocreate a better world.