Much has happened in particle physics since the last (1989) printing of The Particle Hunters. Some of the new discoveries have filled critical gaps in the picture of the world which particle physicists have endeavoured to sketch in the last four decades. This picture, although by no means perfect, is much more complete now than it was a few years ago. Therefore, when Dr Simon Capelin from Cambridge University Press wrote to us, asking whether we would be willing to produce a new and updated second edition of the book, it was difficult to decline.

In undertaking that arduous task we were encouraged by warm responses of readers from all over the world, who have read the book either in English or in some other language (Spanish, Italian, Japanese or Hebrew) and wrote to tell us how they had benefited by it.

A gentleman from Sussex sent us his own theory of elementary particles, which he had conceived after reading our book. A young journalist from Eire who managed to embrace all the laws of physics in one equation, published it in a local newspaper and sent us the relevant issue. A poet sent us a poem in which she recounted the dreams she had after finding out what the world is made of, and a public relations manager in an accelerator centre in the USA told us how the book had helped her to understand the operation of the accelerator and to explain it to visitors.