Hugh Johnson's Pocket Encyclopedia of Wine
I'm reviewing the 1998 version of this, but Hugh Johnson's advice and books are relished year after year. The size is perfect for tossing into a large purse or your glove compartment. I like the organization, with the dark tabs along the edge so you can riff through the book and easily find the section you're looking for.

Yes, you can argue with a particular winery's rating, and what he likes is not at all necessarily what you will like. Still, what you do is compare your wine tastes with his wine tastes. You might find you completely disagree when it comes to Chardonnay, but that you both have the exact same idea about California Cabernet. Whatever it is you agree on, you can now use his guide to help you make great selections.
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