A fascinating book that crams in so much, even if it has an overwhelmingly Anglo-US focus - the Soviet era KGB and East German HVA get a mention. The historical setting is good, using Russia in 1917 as one and Northern Ireland for another. Oddly very little from Israel.

Then the 'new world' intrudes with the demise of the 'Cold War' and the 'new jihadist terrorist' threat taking centre stage.

A few puzzling references appear to non-warfare threats, notably multinationals moving billions and whether in the future there is a national political requirement to spy on them. What would have been the impact of a spy in some of our banks prior to the 2008 "crash" ?

The interplay between HUMINT and TECHINT (in all its varieties) is covered well.

I have made a lot of notes to think further about and some online, anonymous research in 2016.

Yes the author is a journalist and his Amazon bio states:
Stephen Grey is a British writer, broadcaster, and investigative reporter with more than two decades of experience reporting on intelligence issues. He is best known for his world exclusive revelations about the CIA's program of "extraordinary rendition," as well as reports from Iraq and Afghanistan. A former foreign correspondent and investigations editor with The Sunday Times, he has reported for The New York Times, The Guardian, BBC, and Channel 4, and is currently a special correspondent with Reuters. Grey is the author of Ghost Plane.
"Insiders" on both sides of the Atlantic have expressed their admiration for the book, including details they thought were not in the public domain.

Amazon (US):http://www.amazon.com/New-Spymasters...y+stephen+grey

Amazon (UK):http://www.amazon.co.uk/New-Spymaste...s+stephen+grey