Catch 22 by Joseph Heller
I saw Heller at the Hay Festival many years ago and my son, Thorne, was lucky as I got him to sign a hardback Catch 22 for him.
Alongside Kurt Vonnegut Jr Heller is one of the best writers to show that the system sucks and they both do it with humour and intelligence and incredible insight.
I loved this book when I first read it nearly forty years ago – oooh ouch – and I love it still. I buy almost every copy I see – it always sells or there is someone I know who needs it.