This innovative book addresses the need for significance and mattering as a universal human motivation. It examines the impact of significance and mattering, considering how they manifest across our lifespan and in different parts of our lives. Written by a team of eminent authors with expertise in diverse psychological fields, the book explores how significance and mattering extend to almost all social domains, including families, schools, colleges, groups, workplaces, communities, and nations. The book is divided into four main parts, which consider the impact of significance and mattering across the life span, across life domains, across societies and cultures, and in mental health. The chapters outline how significance and mattering power race and gender politics, shape attitudes toward immigration, drive violent extremism, and underlie mental health issues, such as loneliness, and narcissism. The book considers the quest for significance as a fundamental motive in our personal interactions and in how society operates as a whole. Providing a truly comprehensive coverage of a ubiquitous psychological dynamic that affects all aspects of our lives, this book will be highly relevant for researchers, academics, practitioners, and students in psychology, social sciences, education, social work, and therapeutic professions. In addition, the book should appeal to organizational, political, and community leaders and the general public interested in human behavior and social problems.