This topic has been a long-standing interest of mine since undertaking volunteer work in 1999 with victims of the armed conflict in Guatemala. The strength of victims of human rights violations and of the advocates who act on their behalf has constituted the major source of inspiration during this research. This book is based on a Ph.D. thesis successfully defended at the London School of Economics and Political Science (LSE) in November 2010. I wish to express gratitude to Prof. Stanley Cohen for encouraging me to apply to LSE, to Prof. Gerry Simpson for his supervision and to Dr Margot Salomon for her supervision and important guidance during the final stages. I also wish to thank Prof. Manfred Nowak and Prof. Francesca Klug for their invaluable comments in the context of the examination of the thesis. A warm expression of appreciation to my supervisors at the UN Office of the High Commissioner for Human Rights (OHCHR): Jane Connors and Mercedes Morales for their vital advice and support, without which this project could not have been undertaken. I wish to thank the many colleagues and friends I have had the pleasure of working with and learning from at OHCHR, especially in the Colombia Office (gracias) and within the Human Rights Treaties Division and Special Procedures Branch in Geneva. A particularly warm appreciation to Maja Andrijasevic-Boko, Linnea Arvidsson, Therese Bjo¨rk, Elisabeth da Costa, Helle Dahl Iversen, Joana Miquel Gelabert and Katarina Ma°nsson for many shared smiles and for encouragement over the years. I could not have done this without you. For their friendship and inspiring commitment to human rights work, I also thank: Estelle Askew-Renaut, Carmen Bejarano,