This book's one of those ones recommended by work's training department, and it's been on my list for quite some time. So, I saw it going cheap in a charity shop and snapped it up (yet again - I think either people nearby like to buy business books, or, more precisely, like to offload them them to charity shops).
As with most of these popular business books, it fits the stereotype: Written by experts in the field, quite short, but that's not a problem because it wraps up a simple idea, and most of the book is really about exploring that idea in depth, with examples. Oh, and it's quite good.
So, what's this book about? Simply, it's the idea that a negotiation should be about both sides co-operating to come to an agreement, rather than treating it as a competition in an assumed zero-sum environment. So, plenty of understanding of what people are actually motivated by, rather than their demands, being constructive, generating win-win situations, looking to external sources for reasonable reference levels, etc.
It's rather nice to read this book after having worked on a couple of projects where we ended up pretty much taking the approach described in this book. Having accidentally reinvented the approach, the clarification the book provides is very useful.