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 »

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