|summary=Leave reading West's introduction to the end and dive straight into Masterman's formal (but highly readable) report into the activities overseen by the XX Committee for intriguing insights into some of the real successes of WW2 ~ and some of the ideas that came to nothing. West's introduction makes much more sense reading it after you have some idea of what he's talking about. A fascinating historical document that still resonates with what might just be still going on today. Recommended.
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This ''Vintage'' re-issue of Masterman's account of the work of the Twenty Committee is subtitled the ''classic account of World War Two Spy-Masters''. That's a somewhat misleading tease. The book isn't really about the spy-masters, very little information is given about those recruiting, turning, running and protecting the spies. More information ~ - but again relatively little ~ - is given about the spies themselves.
The important word in Masterman's own original title is ''System''. In reading the book, you have to fully understand its context. It is basically a report, written in 1945, assessing the value of using double agents and, having proven there is a value, how best to support the activity. It looks at the pros and cons of the system. In giving an overview of what actually happened from the interwar years through to the cessation of hostilities in 1945, Masterman seeks to set out for future reference, the lessons learned 'on the hoof' as the system developed and evolved.