I bought this thinking it was a great deal on the 4th edition, as the picture of the cover would suggest. It arrived quickly (the ONLY) good point about this purchase) but was the 3rd edition. I requested a return and refund, which was accepted, sent it back, which was an additional cost but certainly much cheaper than the £44.19 I had paid for. I assumed all had been refunded until I looked at my bank statement and nothing was there. I emailed amazon who contacted this company and they said the book hadn't been returned... ha, seems a bit fishy. Luckily the Royal Mail couldn't see what had happened so refunded me *some* of my money. Moral of the story... do NOT buy this!