Jump to ratings and reviews
Rate this book

GCHQ: Centenary Edition

Rate this book
Fully Updated Centenary Edition

GCHQ is the largest and most secretive intelligence organisation in the UK, and has existed for 100 years - but we still know next to nothing about it.

In this ground-breaking book - the first and most definitive history of the organisation ever published - intelligence expert Richard Aldrich traces GCHQ’s development from a wartime code-breaking operation based in the Bedfordshire countryside into one of the world-leading espionage organisations.

Packed with dramatic spy stories, GCHQ also explores the organisation’s role behind the most alarming headlines of our time, from fighting ISIS to cyber-terrorism, from the surveillance state to Russian hacking.

Revelatory, brilliantly written and fully updated, this is the crucial missing link in Britain’s intelligence history.

Audible Audio

Published July 11, 2019

18 people are currently reading
183 people want to read

About the author

Richard Aldrich

75 books8 followers

Ratings & Reviews

What do you think?
Rate this book

Friends & Following

Create a free account to discover what your friends think of this book!

Community Reviews

5 stars
38 (39%)
4 stars
47 (48%)
3 stars
8 (8%)
2 stars
3 (3%)
1 star
0 (0%)
Displaying 1 - 24 of 24 reviews
Profile Image for Mary.
85 reviews44 followers
September 19, 2025
If this is not the shocking truth of things, then I would suggest the 'thought police' in their numbers would have paid an early-morning call on the author a while back. I don't own a tin hat; it's all true.

I'll be brief: stop what you're doing/reading, buy this now and read it now.
Profile Image for Gisela.
60 reviews27 followers
November 16, 2025
You could have this by your bed or in your bag and just read a few pages at a time. The more I read the more shocked I became. I'd say it's essential reading: a few pages at a time.
Profile Image for Martin Turner.
25 reviews11 followers
September 23, 2024
I've not used social media for several years, as is true with my wife and daughters as I have suspected for many a year that the establishment has been monitoring what we say and what we do. Anti-terrorism being the excuse they use.
How little I knew.
If you want to know what is actually happening with us, the innocent, hard-working, citizens, read this.
Profile Image for Tina.
11 reviews17 followers
October 2, 2025
Gulp!

The author, Richard James Aldrich FRHistS, can't be someone throwing lies and make-believe this way and that, he has to protect his reputation. In which case...

... all this is true.

I'll never know who reads this... if you do, I would suggest you read this book.
Profile Image for Lizzy.
3 reviews15 followers
September 13, 2025
A remarkable read. People talk of big-brother and the surveillance state. I've always shrugged and imagined most of it was tin-hat nonsense. Little did I know!
40 reviews2 followers
October 19, 2022
GCHQ is a non-fiction, fully comprehensive history of one of the most secretive government organisations in the UK. For around 100 years Britain has been at the forefront of what is known as signals intelligence, with GCHQ being at the heart of that effort. Government Communications Headquarters is the secret third arm of the British intelligence agencies, along with our domestic intelligence agency MI5, and our foreign intelligence agency the Secret Intelligence Service (SIS), sometimes referred to as MI6. Throughout its history, it has managed to fly under the radar far longer than most other signals intelligence (SigInt) operations such as the NSA which services the United States.

Throughout this book, Aldrich treats us to a rich and very well researched history of British SigInt. From the first introduction of radio wave interception at the turn of the 20th century right through the first real test and triumph during the second world war. Onwards to GCHQ’s extensive involvement in the intelligence arms race of the cold war, and from cold war into hot peace dealing with a post 9/11 world and the advent of the internet and all of the security risks that entails.

One of the sides of the book that I found most interesting was the exploration of the political and economic climate surrounding SigInt. The ups and downs of various Governments, Prime Ministers who took a great personal interest in GCHQ and those that dismissed it and the advice provided but its intelligence gathering efforts. GCHQ seems to have always been rather on the back foot in terms of budget when compared to the likes of the NSA. And yet, it has always punched way above its weight with it being the premiere SigInt intelligence service in Europe.

Richard Aldrich, however, does not simply bathe the service in glory. He seeks to tell as much of the story as is possible when it comes to covert actions. He presents balanced analyses of the various scandals that have befallen GCHQ as well as questioning some of its unethical practices. After the fall of the Soviet Union, the world of SigInt began to move away from covert action against major enemy states and instead began to include non-state actors such as terrorist groups. This was of course kicked in to overdrive post 9/11 and then again with the 7/7 bombings. A lot of the post 9/11 actions that are written about in this book will make you question the lengths that Government surveillance goes to. Even the most ardent supporter of strict security and scrutiny would question the idea of British intelligence aircraft circling British cities hoovering up every scrap of mobile phone telecommunications data.

Overall, this is a truly fascinating dissection of a little known topic to most people have probably not heard of. Aldrich presents a rich history of British SigInt being at the forefront of technical progress whilst also discussing the less savoury aspects of the secret intelligence world. If you are at all interested in spy stories, the cold war, or the modern battleground that is cyberspace, then this book is for you.
Profile Image for Zara.
10 reviews10 followers
October 1, 2025
There's not much that can pull my thoughts from my job. This did. It is difficult to ignore how knowing what 'they' get up to all day, every day.

Watch what you say on the phone, be that a mobile or a landline: someone IS listening.
Profile Image for Sara.
6 reviews2 followers
September 26, 2025
The truth behind what 'THEY' do behind our back. I will be seeking out an NSA equivalent.
Profile Image for Rose.
1,537 reviews
January 26, 2020
It proved a fascinating look at an area of British history I had never really thought much about. Since I know so little about it (and, due to it's nature, there are probably plenty of things that are still not available to the public) I don't know how comprehensive the book really is, but it seemed to give a fairly seamless overview of this breed of intelligence since WWII. At times the writer seemed to favour GCHQ and Britain in the tone of his writing, but he seemed to be making an effort to give a balanced view of events all the same, and I think as long as one stays conscious of the fact that there's probably much more to be said by every side involved in some of the events commented on then I don't think it gives too one-sided a view. While the earlier portions of the book (focusing on earlier parts of history) can be simply viewed as interesting because of the distance of the events, more recent views are a little scarier. The end of the book delves into the more controversial approaches to intelligence in the present day, and offers quite an in-depth analysis of different sides of the problem. Oddly, I thought this was the book where bias came through the least - perhaps because it is easier, when writing about earlier parts of history, to cast GCHQ & its workers as heroes, where as in the modern world the waters are muddier. All in all, a worth-while read that presented a mysterious and complicated topic in a way that was easy for the layman (or woman, in my case) to follow.
Profile Image for Sheila.
16 reviews5 followers
October 18, 2024
I never thought I would be the person to say this about a book:

You have to read this!
Profile Image for Andrew.
535 reviews15 followers
September 26, 2025
I listened to this book via Audible.

GCHQ covers the history of the UK's signal intelligence agency, from its creation to almost-present-day. It reveals a lot that I certainly wasn't aware of, including its role in cracking ENIGMA.

The biggest detractor here for me was the organization of the chapters. The way they're laid out is not purely chronological, so there's some jumping back and forth in time and repeating of information in different sections. It requires paying close attention to dates and details which sometimes makes it difficult to follow.

Apart from that, the book is very informative and educational. I learned almost as much about SIGINT as I did about the GCHQ itself. There's also a lot of intersection with global politics and how intelligence sometimes plays a very different role than I would have expected in international relations.

Overall, I enjoyed reading GCHQ, even if it was occasionally confusing. If you're interested in intelligence agencies and what they're up to, give it a read.
Profile Image for Jan.
1,258 reviews
February 15, 2021
Energetic and insightful. As always with this genre you are left wondering about how much of the full story is being exposed. Nonetheless it is very interesting to follow the story from Ultra-code breaking in Bletchley park through the multiple dramas of the Cold War till today.

I believe Mao spoke about the guerilla being the fish swimming in the sea of the people. If the people is the sea the GCHQ and NSA gobbling up our meta-data probably makes sense to track the bad guys and girls, but how should we feel about the meta-data - and the content - being used to model, predict and eventually shape the behaviour of the rest of us? The similarity to Zuboff and her analysis and warnings in Surveillance Capitalism are striking.
5 reviews
March 10, 2020
Lots of this book read as a detailed time line focused on the last 80 years of GCHQ and its involvement in the world of signals intelligence. It dips into prominent stories along the way and covers its relationships with other agencies. While there aren't any revelations it does cover some areas in greater depth (e.g. Snowden) and details the impacts on GCHQ. The latter parts of the book start to introduce concepts that have had a great impact on personal and state security but also while the technology is forever improving how lots of things don't change.
22 reviews
December 30, 2025
Not for everybody, but this book hits my nerves. Richard Aldrich speaks about something seldomly written about with such passion and knowledge. This book becomes is one of those you want to keep based on facts and dramatical events. So much knowledge, research and last but not least, probaly alot of humanint and analysis of sigint buildt up over many years. This book is highly recommendable with a lot of new learning and insights from "the other side" in every chapter.
I lift my hat for Richard Aldrich hard work. Clear 5 star!
14 reviews25 followers
July 29, 2024
You want to know the truth behind data-collection:
from foreign agents?
from foreign embassies?
from foreign nationals?
from foreign countries?
you might get a good idea of what goes on after picking this up.

You want to know the truth behind data collection:
from you, from your mum, your dad, your wife, your husband, your children?

Take a look inside: it's scary.
Profile Image for Amelia.
14 reviews14 followers
November 30, 2025
I read this twice: if any of this, even a teeny-weeny bit, was hokey-pokey I'd have thought the government would have sued the publishers into the next millennium and screamed defamation - as such, it's all very, very, very, true.

My thoughts on this work are: "Crikey."

Are we any better off than the North Koreans?

62 reviews1 follower
March 2, 2021
Completely absorbing, fascinating and disturbing read. It is a shock to peer into the shadows and get a glimpse of how the world really works and how the strings are pulled. Who needs conspiracy theories when you can read it for real in this remarkable book. Highly recommended.
Profile Image for John Howard.
8 reviews
Read
October 30, 2025
Read this and then go back and start with James Bamford’s Puzzle Palace about the NSA and work forwards. Also thoroughly recommend Frances Stonor Saunders
Who Paid the Piper?: The CIA and the Cultural Cold War as well.
Profile Image for Rodney Hawkins.
7 reviews
April 22, 2020
It get's a bit long in the tooth - but very interesting - especially the chapters on the US - UK alliance, the infiltration of European partners and the Turkish events. Interesting indeed.
Profile Image for Yasir Noori.
41 reviews
March 7, 2021
A detailed account of the history of the GCHQ. Only recommended for readers that are highly interested in this subject due to its length.
Profile Image for Dottie (I'm not dotty).
26 reviews12 followers
January 30, 2025
You might say, "Why try and control the release of my personal data, they know everything there is to know about me already?

I say, "You should read this book."
Profile Image for Steve.
28 reviews12 followers
March 17, 2025
I've been suspicious of our walls having ears for many a year. Friends have giggled and called be cynical and at times a conspiracy nut.
I was scratching at the surface. This is mind-blowing.
Displaying 1 - 24 of 24 reviews

Can't find what you're looking for?

Get help and learn more about the design.