This book examines the nature of participatory research in the social sciences and its role in increasing participation among vulnerable or marginalised populations. Drawing on engaging in-depth case studies, it examines the ways in which inclusion and collaboration in research can be enhanced among vulnerable participants, such as those with profound learning difficulties, victims of abuse and trauma and multiply vulnerable children and young people, and shows how useful it can be with these groups. The book will be an invaluable resource for students, researchers and academics in many countries who want to put participatory research methods into practice.