More than 21 billion of unaddressed printed matter distributed in France in 1995! In Europe, like in France, unaddressed printed matter is a very special advertising support, thanks as much to the amount distributed in letterboxes, as to the market dynamics that it represents. Until recently, unaddressed printed matter had been a media that was certainly very much used by advertisers, but often underrated, and whose audience was not measured at all. How can we master the supply of unaddressed printed matter? How can we measure a number of real contacts between individuals and paper advertisements?