I really admire Adrian Furnham and I have many of his books.My favourite is Head and Heart Management, a collection of short essays that can really strike a chord with the HR professional who doesn't want to divorce the reality of people from the needs of managing a business.
A fantastic book for those starting a career in reward is Armstrong and Murlis' Reward Management'. It's not the sort of text you can sit and read cover to cover with a glass of wine but informative, interesting and ressuring.
Despite reading a lot for my job I also read for pleasure. One book I go back to fairly often is Richard Branson's autobiography, Losing my Virginity. It tells a brilliant story of a man's rise despite numerous obstacles along the way. Love him or hate him you cannot deny his success.