To the trained eye of a winemaker, a vineyard is a tapestry of dozens of micro-sites: This hillside parcel gets the best sun, that one has distinctively chalky soil, another patch nearby has been replanted with new vines. The art of winemaking is in coaxing the best out of each parcel, and then blending them together to create a harmonious whole.

That means vinifying dozens of unique batches in the cellar and then bottling the ones that turn out best. For wine lovers, it can mean great bargains. Batches that don't make the final cut—even though their contents were grown and vinified side by side with the highest quality batches—are often bottled under a separate label, or "second wine."

These aren't low-quality cast-offs. The second wines are generally made from younger vines and are aged for less time, but they share many characteristics with their famous siblings. Think of them as softer, more approachable versions of the first wine—at a fraction of the price. A bottle of Latour may cost a couple thousand dollars; the chateau's second label, Les Forts de Latour, runs $275 for the excellent 2005 vintage. (See some of the best in our slideshow.)

The second wines of the top Châteaux, including Les Forts, Château Margaux' Pavillon Rouge du Château Margaux, and Château Haut-Brion's Bahans Haut-Brion (renamed Le Clarence de Haut-Brion starting with the 2007 vintage), can be better than the "first" wines of lesser estates.  

"Second wines are representative of the first wine, but at a better value and can be drunk earlier," says Roger Dagorn, wine director of Chanterelle in New York and a Master of Wine. "That's the beauty of these wines."
 
Second wines are most closely associated with Bordeaux, where they were made as far back as the 1800s. The practice became widespread in the late 1980s, when competition and a renewed focus on quality drove winemakers to be more selective, using only the very best fruit and batches of wine for their gran vins. Sometimes just a small portion of the vineyard's output would make the final cuvée.

Rather than sell the leftover wine to bulk dealers, the châteaux began blending second wines. This was profitable for the producers, and gave customers a more affordable way to get a taste of the signature wine.

"Second wines are some of the best values coming out of Bordeaux," says Jeff Zacharia, president of wine retailer Zachys. A 2005 Carruades de Lafite Rothschild ($268 at Zachys), for example, is a bargain compared with a Lafite of the same vintage ($1,500), especially considering the latter won't be at its prime for years to come. Carraudes is less complex, perhaps, but a serious, full-bodied wine.

Virtually every Bordeaux producer today makes a second wine. Zacharia points to La Réserve de Léoville-Barton ($50), the second to Léoville Barton ($250 for the 2005); Les Fiefs de Lagrange ($27), second to Lagrange ($75 for the '05); and Les Hauts de Pontet ($55), second to Pontet-Canet ($190 for the '05), as great values. Regions from Australia to Spain's Priorat are offering second wines as well, though many don't aggressively market them, so as not to detract from the premier offerings.