Positive Psychology has become a major approach to the scientific study of individual, social, community and cultural processes. This book includes a selection of papers presented at the 3rd European Conference on Positive Psychology, organized in Braga at the University of Minho, Portugal in 2006. The title of the book reflects its main purpose and a main concern for positive psychology - Understanding Positive Life - balanced between the two scientific pillars, the research and the practice. Several contributions concerning theory, research and practice are presented in three different parts: Happiness, Well-being and Life Satisfaction (PartI); Performance, Coping and Quality of life (PartII); and assessment, Intervention and Practice for a Positive Life (PartIII). Each part includes eight chapters, with a great diversity of authors coming from different countries.