Abstract: A web advertiser may geographically target internet display advertising by selecting geographic parameters. Fragments of geographic location data are supplied by or inferred about a computer user accessing a web publisher's web site. User information is transmitted by the web publisher to an advertising server, where it is supplemented by comparison with a geographic information database. User information is then compared to geographic parameters supplied by the advertiser. If a match is found, a geographically-targeted advertisement is transmitted to the user. If no match is found, a default advertisement is transmitted to the user. Advertising inventory from many advertisers may be aggregated on the advertising server and delivered through many web publishers to users in specified geographic locations.