The Ark has always been consideredone of the theoretically-heaviest defenses in meeting the Ruy Lopez, thoughalso the most exciting and definitely the most beautiful of all.  It requirestactical vision, good calculation and memory, but not just from us - from the Whiteside too. Let's not forget that! I also must say that no good lines are absentof theory, so if we’ve decided to learn something "finally", I argue that itcan very well be an ambitious, double-edged line too! :-)I should also mention that thisbook is a complete Black repertoire starting from 3. Bb5 a6, the exchange variation being the first chapter. Thepublisher and me agreed on offering a full package, one that should proveuseful for many years to come!