"Primeur"  is the release and sale of wine before they are bottled and ready for physical delivery. The terms of the exchange (price, quantity and delivery date) are settled at the time of the sale (during Spring) and the wines are delivered when they are bottled, usually 18 to 24 months after the harvest. During this time, the wines will complete their maturation process, usually done in barrels. Bordeaux is the historic place of the En Primeur campaign, with the commercialization of the Grands Crus, but this type of sale is also developed in Burgundy, Languedoc or Loire Valley. There is a lot of frenzy during this campaign because usually the most prestigious Chateaux of Bordeaux sell exclusively their wines via the En Primeur system. Typically, wine merchants and wine critics are invited in Bordeaux to taste wines that are too young to drink. The final wine is often a blend of several grape varieties, so the winemaker will try to craft an approximate blend to sample. Based on the initial sample, the wines will be giving a preliminary “score” or wine rating based on the expected quality of the wine once it is bottled, released and has had time to mature.