Futures: A wine sold to consumers several months, sometimes years, before its release. The initial futures offering is touted as a lower price than will be offered when the wine officially hits the market. The practice is most commonly associated with Bordeaux's annual en primeur campaign.
En Primeur: Also known as "futures" in the American market, en primeur sales typically refer to Bordeaux, but not exclusively. The en primeur offerings are a winery's first offer of a particular vintage, when the initial price is set, and offers buyers the opportunity to purchase wines before they are released.