MOST LIKELY: Choose wisely and these heretofore anathematized combinations will not ruin a meal. A light red, such as a Pinot Noir or a Beaujolais, works well with "meatier" fish, like tuna, salmon, and swordfish. And an assertive white, like a California Chardonnay, can be an acceptable partner for steak.

WORST CASE: If you're eating a delicate fish and you drink an inky Cabernet Sauvignon, chances are the wine will overpower the subtle flavors of your main course, according to Ray Isle, managing editor of Wine & Spirits magazine. If you drink a light Sauvignon Blanc with steak, he says, the wine may not taste like much more than alcoholic water.