Dominic Abrams & Michael A. Hogg 
Social Psychology of Inclusion and Exclusion [PDF ebook] 

This book is about the social psychological dynamics and phenomenology of social inclusion and exclusion. The editors take as their starting point the assumption that social life is conducted in a framework of relationships in which individuals seek inclusion and belongingness. Relationships necessarily include others, but equally they have boundaries that exclude. Frequently these boundaries are challenged or crossed. The book will draw together research on individual motivation, small group processes, stigmatization and intergroup relations, to provide a comprehensive social psychological account of social inclusion and exclusion.