Recommended. One of the authors Martin Ingram(a pseudonym) was a member of the FRU(Force Research Unit),a british military intelligence outfit which recruited informers within northern irelands paramilitary organisations. This book looks at the cases of many informers but has most details of the 2 most famous. After chapters on the authors FRU training in recruiting and running informers,we get a number of chapters on STAKEKNIFE. This informers name has been in the public domain for nearly a year,and the book confirms his identity. STAKEKNIFE was the supreme irony. He was the deputy of the Irish Republican Army's internal security unit(the so called nutting squad),which was tasked with finding informers within the IRA. It lists 35 alleged Informants who were executed by stakeknife,so as to maintain his cover within the IRA. The book also confirms the identity of other informers,some are named,others are given pseudonyms whilst their activities are described. There are a number of chapters on Brian Nelson,who infiltrated the loyalist/protestant Ulster Defence Association. Great value.I recommend this book.