Out-of-Home (OOH) Advertising is essentially any type of advertising that reaches the consumer while he or she is outside the home. This is in contrast to broadcast, print, or internet advertising which may be delivered to viewers while they are outside the home, but are usually viewed in the home or office. Such locations would include tradeshows, newsstands, hotel lobbies, or hotel rooms.

Out-of-home advertising products are divided among three primary categories: Billboards, bus benches, wallscapes, fleet media, skywriting, flying banners, movie theaters, and digital signage networks. OOH encompasses outdoor advertising but extends to the indoors as well (such as ads in malls). Digital signs are the latest devices in the evolution of out of home advertising.

With media rapidly changing, a dynamic new electronic medium has emerged: Ad-supported networks that deliver compelling, informative content along with full-motion video advertising. These networks include both in-store retail networks and digital, wireless narrowcast networks.

Alternative out-of home media is staying in tune with fast-paced and elusive American consumers, who are spending more time than ever outside their homes. Ad spending on these media has experienced accelerated growth since 2006. Growth was driven by accelerating expansion in video advertising networks, digital billboards and ambient advertising, which are enabling advertisers to engage more mobile consumers in captive locations.

Marketers are returning to the great outdoors. Frustrated by the declining ability of television to deliver mass reach that is cost-effective, advertisers are putting renewed emphasis on reaching people when they are away from home.