Whitewater Paddling: Strokes & Concepts (Jackson, Eric, Kayaking With Eric Jackson.)

Eric, for the most part, focuses on pure paddling technique and skips any superfluous information.

Using the exercises Eric recommends here will certainly improve your river running.

If whitewater kayaking is your interest, this is the book
Eric Jackson has put together the most concise and well thought-out book in modern kayak technique to have come out in years. An experienced class V+ kayaker myself, I found improvements I could apply to my every paddlestroke from this book. Even expert boaters will benefit on key points regarding modern school techniques from catching eddies and snapping sprayskirts to finding the optimal pressurization for floatbags. A must read for all serious paddlers.

Next best thing to an EJ clinic
If you can't take an EJ clinic, this is the next best thing. This book discards much of the "old school" of kayaking which was appropriate for older, longer boats, and replaces it with newer, smarter techniques appropriate for today's fast-turning playboats. Eric clearly understands the physics of kayaking, and communicates this to his readers in a concise, easily understandable style. This book is a wealth of information in a small package.