Our virtual LEO I project with CCH is a finalist in the @bcs UK IT Industry Awards in the Charity Project of the Year category. We are very hopeful as it is a very innovative use of new technology to bring to life old technology for younger generations

Exciting news about the Virtual LEO project! Read More »

Late last year we received the sad news that Ray Shaw, the last of the original LEO I design pioneers had passed away.

A copy of his Obituary can be found HERE. On 20th February John Daines presented material via Zoom remembering Ray and a recording of that can be found on the LEO Website

Remembering Ray Shaw Read More »

LEO Matters Issue 12, November 2022 has been published and circulated to Members and others via email. It can be downloaded by following the download link on this page .

Issue 12 includes the sad news that Peter Hermon, one of the best know and very talented IT professionals in the business, and a LEO Pioneer, died on 1st November 2022 and the Obituary from Computer Weekly is on the “In Memoriam” page and can be viewed here as well as a piece in Issue 12 itself.

LEO Matters issue 12, November 2022 Read More »

A Review By

Robert M. Davison

Dept of Information Systems, City University of Hong Kong, Kowloon, Hong Kong Email:


Review of “LEO remembered—By the people who worked on the world’s first business computer”

Edited by Hilary Caminer and Lisa-Jane McGerty. ISBN: 978-1-3999-3359-9

Robert M. Davison

Dept of Information Systems, City University of Hong Kong, Kowloon, Hong Kong Email:

In this much revised and extended second edition, the editors have compiled a historical account with over 80 contributions from many of the people who were associated with the Lyons Electronic Office (LEO) project from its inception in 1949 through the 1950s and 1960s. It hardly need to be said, but for those of you not in the know, LEO was the world’s first business computer. It is remarkable to realise that the events that surrounded the development of LEO took place over 70 years ago. The book includes archive photographs from the period.

The LEO story has been told many times, in print, and also in film: see the YouTube version at https://www. The historical background and early days of LEO are presented in a remarkably non-technical fashion in this extensive and charming set of recollections that collectively portray the LEO project as one of collective endeavour. The accounts in the current volume are illuminating and inspiring, but I have to emphasise that this book is more a collection of reminiscences than anything scholarly. Indeed, this is perhaps one of the most attractive features of the book—it allows the human side of LEO to flourish. Thus, in reading the text one witnesses the thrills (and spills) of working on a huge mainframe computer at the very dawn of the age of business computers. We read how ‘bugs’ flew through the window and got stuck in valves, of how rain was equally problematic, and how hardware problems could be fixed with a screwdriver. We have to remember that as pioneers in mainframe computers, the designers, programmers and other technicians were not able to refer to past practice elsewhere: my sense is that they relied extensively on ‘seat-of-the-pants’ logic and fixed problems as they arose to the best of their imagination and ability.

The overall effect of reading this book is to glean an unexpected insight into what it was like to work at the cutting edge of technological innovation, and as we look back, to realise that the innovations of that time inspired the innovations that followed all the way to the present day. I very warmly recommend this delightful book. You can obtain copies at ₤8 + postage from the LEO Computers Society. Please write to LEOremembered@leo-computers.

Wiley Book Review of LEO Remembered Read More »

A LEO Computer Society Zoom was held on 19th November 2022 when Anna Ryten, a Partner in Architects Mountford Pigott, and Kerry Lemon, an artist retained to create an artwork about LEO and Lyons presented the proposals for the re-development of 66 Hammersmith Road. This development project includes substantial work to record and commemorate the history of the Lyons Company and the Lyons Electronic Office (LEO) Computer.

To view a recording of the session click here

Development Plans for 66 Hammersmith Road Read More »

LEO Remembered has been substantially revised and added to by Hilary Caminer, of the LEO Computers Society and Lisa McGerty of the Cambridge Centre for Computing History. There was an event on 28th September on Zoom to launch the new book . You can also order copies of the book at the link below at GBP8 plus postage. Please specify quantity and address (especially country) for delivery if you want to order and we will send a cost quotation and instructions for payment.

Order your copies here .

A recording of the launch event can be viewed here

Launch of the massively revised LEO Remembered on 28 September Read More »

The LEO Computers Society and partners Centre for Computing History are delighted to announce that their film about LEO, the world’s first business computer has won the Association of British Science Writers (ABSW) Video of the Year Award 2022. 

LEO, otherwise known as the Lyons Electronic Office, was a pioneering British computer developed in the early 1950s by J. Lyons & Co., famous for tea, cakes and the teashops that were once part of the fabric of British life. 

The film was commissioned as part of a lottery-funded project ‘Swiss Rolls, Tea & the Electronic Office’, which is preserving, cataloguing and making accessible the heritage of this remarkable machine so as to raise awareness of this relatively unknown British story. 

Judges commented that the film was “an absorbing and textured piece with excellent and evocative archive footage”. It aims to introduce a whole new generation, from secondary school age upwards, to the remarkable story of the birth of a technology that, today, we take for granted.

Lisa McGerty, manager of the project said: “We’re honoured to have had the LEO film we commissioned – and which was expertly made by Richard Hollingham and Jamie Partridge of Boffin Media – recognised as the Association of British Science Writers’ Video of the Year. LEO’s story really is remarkable and it is a privilege for us to work with some of the surviving pioneers on this project, as well established film producers like Boffin. The first LEO computer was an astounding feat not just of engineering but also of vision by a company that had the foresight to recognise just how computers could revolutionise business at a time when computers didn’t really exist. Everyone should know about it.”

The film is freely available to watch at It will be signposted to schools and colleges as part of The Centre for Computing History’s learning programme.

1. The film has been created by Boffin Media, an award-winning production company specialising in science and space. The Producer is Richard Hollingham and the Director is Jamie Partridge.

2. The LEO Computers Society is committed to promoting and protecting LEO’s history. Membership of the Society is open to all ex-employees of LEO Computers and its succeeding companies, anyone who worked with a LEO computer and anyone with a specific interest in the history of LEO Computers. Among its members are pioneers from the very early days of computing and membership is currently free of charge. Visit Follow @leocomputers51.

3. Established in 2006, the Centre for Computing History is a charitable heritage organisation with a strong focus on learning. Since opening in Cambridge in August 2013, the Centre has helped people understand how tech has shaped the modern world and revolutionised the way we live, work and play through interactive displays and exhibitions, our schools programme, learning events and workshops, and an astonishing collection of computers old and new. Visit Follow @computermuseum 

4. Using money raised by the National Lottery, The National Lottery Heritage Fund inspires, leads and resources the UK’s heritage to create positive and lasting change for people and communities, now and in the future. Since The National Lottery began in 1994, National Lottery players have raised over £43 billion for projects and more than 635,000 grants have been awarded across the UK. Follow @HeritageFundUK on Twitter, Facebook and Instagram and use #NationalLotteryHeritageFund

 For further information on the museum, the Society, the LEO project or for images, please contact: Lisa McGerty (, 01223 214446 / 07825 794791) or Peter Byford (, 07944 038489).

We won Video of the year Read More »

Jason Fitzpatrick the CEO of the CCH gave LEO Computer Society members a virtual tour of the exhibits at the Museum on 27th April. The meeting was held on Zoom and recorded for those who wanted to attend but who were not able.

The recording is now available on this Website and can be viewed by following the link above. In addition an updated version of LEOPEDIA as at 30th April has been also uploaded to the Website

The Zoom Video can be viewed by following This Link and the updated LEOPEDIA Here

Zoom Recording of a tour of the Centre for Computing History now available Read More »

It is with great regret that we have to report that Mary Coombs, one of the LEO pioneers passed away  on 28thFebruary 2022 at Stoke Mandeville Hospital, at the age of 93. Mary was the World’s first female business computer programmer joining the LEO team in 1952. We will let members know when the funeral is arranged. Mary was a good friend of the society and will be sadly missed. You can see Mary’s obituary on the CCH Website Here. Other published Obituaries include The Times, Computer Weekly, Computing, BCS, The Register, The News Trace, The Guardian , The Daily Telegraph, The ACM, Wikipedia, Bucks Free Press, Elective College and Radio 4’s  Last Word on Friday (18th March) at 4p.m. , repeated on Sunday (20th March) at 8.30 p.m. – and available as a podcast thereafter -Listen at:

There is also a recording of a recent Zoom meeting held to remember Mary –Zoom Recording and copy of the presentation deck used by Hilary Caminer Presentation

Mary appeared in our/CCH recent film about LEO remembering the early days of LEO (and if you haven’t seen it or want to watch it again go here )and there was a short BBC Witness History feature made about her- available for viewing at and her school, Putney High School also celebrated her at:

For those interested in Mary’s life you can read a transcript of her Oral History at the British Library here.

Picture of Mary below. Copyright Mike Hally/LEO Computers Society

Mary Coombs (Updated 26 March with additional links) Read More »

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