The book is a great guide to understanding the different models used on Wall Street to capture the intricacies of modeling and pricing derivatives. The books focus of using models as a tool and NOT a solution is a great reminder to both traders and salespeople.
This summarized when the author describes the pricing of a digital cliquet.
"Those sellers using local Vol models will certainly value a digital cliquet at a lower price than sellers using stochastic volatility. Perversely then, those sellers using an inadequate model will almost certainly win the deal and end up short a portfolio of misvalued forward-starting digital options. OR even worse, a dealer could have an appropriate valuation approach but be pushed internally by the salespeople to match (mistaken) competitors' lower prices."

The Volatility Surface is an-ultra modern account of derivatives pricing and hedging. Indeed of the fifty-two bibliographical references a mere twenty were written before 1999. The book makes the case for option pricing models which incorporate randomness into stock price volatility (stochastic volatility) and jumps into stock price movements. By themselves these are not new models, but a coherent understanding of their relationship to the dynamics of the volatility surface and to derivatives valuation is new, and Gatheral does an admirable job of presenting a great deal of the most modern work in this area - including some of his own - in one place.

The topic is necessarily mathematical in nature and Gatheral spares the reader nothing of the full-on mathematical treatment; but he nevertheless manages to distill the essence of the most important mathematics into easily accessible, intuitive explanations that supplement the readers understanding. Thus this book should have broad appeal to practitioners of all levels, especially traders and those familiar with the basics of derivatives valuation. Gatheral succeeds in this vein so well, I believe, because he is a first-rate quant and a a long-time senior quant at Merril Lynch.

The book gives an excellent treatment of the relationship between stock price dynamics which actually explain option prices observed in the market and the necessity of studying the volatility surface to have a complete understanding of derivatives valuation. He does a great job of justifying the key models he reviews and then studies the implications for derivatives valuation.

As an expert practitioner, his choices reflect what is really out there in the market, so readers should pay attention. As a first rate quant, his mathematics and his grasp of the literature on option pricing will expose readers to the best of the best.

Of particular note is his last chapter on volatility instruments, in particular variance swaps, volatility swaps and options on volatility. This is an important market that was just getting started in the late 1990s but has burgeoned into one of the most active and important markets in equity derivatives. This chapter is a must for anyone interested in understanding the subtelties involved in understanding variance swap and volatility swap valuation, and is alone worth the cover price.