This book presents rich and illustrative empirical material on the use of liaison offices in police cooperation. The authors, both eminent academics and seasoned practitioners (and in some cases from a dual academic-practitioner background), present their findings from a wide range of geographical and functional viewpoints. Students and law enforcement professionals are made familiar with the blue web of policing across the world. This book offers them a considerable variety of perspectives, ranging from academic to professional, from institutional to informal, and from sociological to psychological. Together the detailed accounts form an inspiring collection on contemporary practices of liaison officers that not only includes original empirical research, but forms a work of reference as well as a unique textbook for students of international security and policing.