Why collect wine when more than 95% of the world's wines are meant to be consumed within a year or two after release? I can give you two compelling reasons: first, a small percentage of the greatest wines--mostly reds, but many dry white and sweet wines, too--need anywhere from a few years to several decades to achieve their mellow, multifaceted maturity. By then you won't be able to find them or afford them--unless you already own them. Second, the wines you age yourself will probably be in better condition than most older bottles you'll find withering away on retailers' shelves.

All you need is a place that is dark, humid but not too damp, reasonably cool (preferably below 60 degrees but definitely below 70) and safe from daily temperature fluctuations. That, plus a few suggestions to help you avoid the most commonly made mistakes.

BEGIN WITH A GAME PLAN: Some wine lovers buy without making a realistic estimate of their future needs and quickly accumulate more bottles than they can possibly drink over a lifetime. Other collectors cellar too many wines that mature quickly and fade, or overload on one type of wine.

Do some reading, or take a course on the world's major wine regions, or join a wine club that holds frequent tastings before you embark on collecting. Tastings of older vintages can show you what to expect from the wines you are laying down. If you realize now, for example, that you prefer the youthful, spicy red fruit flavors of Pinot Noir to the earthy notes this variety shows in its golden years, you won't waste the time and space aging them.

DON'T OVERLOOK WHITE WINE, BUT CHOOSE CAREFULLY: It's a matter of personal taste, of course, but as a rule of thumb you may want to stock your cellar with a rough ratio of three reds to one white. Remember that most white wines don't reward extended cellaring and that it's always possible to find an excellent, ready-to-drink young white wine at your local shop. Moreover, many dry whites--with the notable exception of some top Chardonnays and Rieslings and Loire Valley Chenin Blancs--quickly lose their freshness and begin to oxidize if subjected to less-than-wonderful storage conditions. On the other hand, far too many of the world's greatest, collection-worthy whites are consumed before they have reached their flavor-filled potential. A young Alsatian Riesling might be austere today, offering only a hint of its future richness and personality. How can you know which whites to cellar? Ask around, read up and, best of all, taste for yourself.

DON'T OVERBUY BORDEAUX: Red Bordeaux has traditionally been the foundation of most great cellars--owing not only to the wine's slow development and legendary longevity, but to its track record for price appreciation. (Case lots of classified-growth Bordeaux from the best years remain the safest investments in the notoriously conservative auction market.) If you're cellaring wine to savor rather than resell, keep in mind that a top-notch red Bordeaux may need at least a decade of aging, and may go through a muted stage during which it will disappoint your expectations.

Some non-Bordeaux, world-class reds to look for: Hermitage and Côte Rôtie from the Rhône Valley; Italy's Killer Bs: Barolo, Barbaresco and Brunello; and California's Cabernet Sauvignons. Red Burgundy, though tricky to buy due to high prices and limited production, can be transcendently good, and is infinitely versatile with food. The underappreciated wines of Provence and the Languedoc deliver an exhilarating range of spicy, herbal flavors. Spain's already well-aged Rioja reservas and gran reservas offer the elegance of claret without the weight--or the wait. Many of the wines above will provide delicious drinking soon after reaching wine store shelves, yet can still improve in bottle for a decade or more.

DON'T LOSE IT ON A SINGLE VINTAGE: Collectors often trample one other in a rush to acquire wines from vintages hyped by the wine press--almost invariably the superripe years. Yet these vintages frequently yield wines that are fiery with alcohol or short on balancing acidity. Drought conditions common in hot years can produce tannic monsters that may require decades to soften. Although the so-called great years may be your best bet for investing in wine, they do not always provide the most user-friendly bottles to enjoy with a meal. Good wines from less ripe vintages will often prove far more versatile with food because of their thirst-quenching acidity and subtler flavors.

REMEMBER SWEET AND FORTIFIED WINES: Just as no self-respecting food lover would think of leaving the table after the meat course, no wine lover wants to end a great meal on a dry note. The best Sauternes, along with late-harvest wines from Germany, Alsace and the Loire Valley, are ideal candidates for cellaring because they require a decade or two of aging to unleash their volatile esters. But because these lovely "sticky" wines are generally made in small quantities, they tend to disappear early from retail shops and thus deserve space in your cellar. So do vintage ports. These special-occasion fortified wines can take up to 25 years to reach their full, mellow maturity and can last for generations. You may drink only a couple of bottles of vintage port a year, but no serious cellar is complete without them.

THINK BIG, THINK SMALL: At a dinner party for eight, a bottle of wine (750 ml) will give everyone one small glass; a magnum (1.5 liters) will please your guests twice. Magnums also age more slowly due to their greater mass. And, a few magnums of nutty, mature Champagne will dazzle your guests on special occasions.

It's also wise to think small. Sometimes a half-bottle is all you want, or a half bottle of white for starters and a half bottle of red for the main course. Half-bottles of luxury dessert wines are a perfect size, since such rich wines are best served in small doses. Wines high in sugar, alcohol and acidity are more resistant to oxidation, so you should not have to worry about premature aging in smaller bottles.

TASTE 'EM IF YOU GOT 'EM: How do you know if a wine is ready unless you taste it? Pop a cork from time to time, and judge for yourself. Thanks to later harvesting and modern winemaking techniques, today's wines are often accessible in their youth, even if they are capable of extended aging. Besides, storage conditions vary and your wines may reach maturity a lot faster--or slower--than the vintage chart suggests.

The Well-Rounded Wine Cellar

Reds (75%):75 bottles

Bordeaux 23

Red Burgundy 12

Rhône Valley 10

Provence/Languedoc 3

Piedmont/Tuscany 8

Spain/Portugal 3

Port/Madeira 2

California Cabernet 5

American Pinot Noir 2

Other domestic reds1 3

Other red table wines2 4

Whites (25%): 25 bottles

White Burgundy 8

Alsace Riesling 3

German Riesling 4

Champagne 1

West Coast Chardonnay 2

Dessert wines3 3

Other white table wines4 4

1 California "Rhône clones," Merlots and Zinfandels; Washington State Cabernets and Merlots.

2 Other Italian reds, Cabernet and Shiraz from Australia, Southwest France, the Loire Valley, etc.

3 Sauternes and late-harvest wines from the Loire Valley, Alsace and Germany, etc.

4 Dry wines from Bordeaux, the Loire Valley, Alsace, Northeastern Italy, Austria, Oregon and Washingon, Australia and New Zealand, etc.