Brut Vintage Champagne is a Champagne produced from grapes solely from one vintage. Each Champagne producer has the right to declare a particular vintage; some vintage such as 2002, considered a classic, was declared by virtually every producer, while 2005, thought to be a lesser vintage, was declared only by some producers.
As a vintage Champagne is limited to the fruit of a single year and not several years, as is the norm, production is limited and the price is more expensive than a non-vintage Champagne (in most cases). Depending on the type of vintage Champagne (a prestige cuvée for example as opposed to a standard vintage offering), aging will vary,anywhere from three years after release to twenty.
It is important to remember that a vintage Champagne is not necessarily better than a non-vintage; rather it is different.