Representation Networks – also known as Rep Firms – often don't want to be known as ad networks. These companies follow a markedly different model from most networks, focusing on selling the inventory from a relatively select set of websites instead of looking to sign up more and more sites of whatever quality, content or style. To a degree greater than with broader-based networks, a Representation Network functions as a sales force for the sites it represents. Many of these networks represent only a few hundred sites, although others number their member sites in the thousands.

Reach is achieved through reseller agreements, which allow Representation Networks to place ads on a site affiliated with another network. Even so, by working with Representation Networks, an advertiser can feel more confident that its brands will not be associated with questionable content or unsuitable websites.

Examples include:
24/7 Real Media
Ad Pepper Media
AdBrite
Addynamix
AdOn Network
Adtegrity
BlogAds
BURST Media
ContextWeb
CPX Interactive
DRIVEpm
Federated Media
Future Games Network
Games Banner Network
Gorilla Nation
MaxOnline
Netshelter
Revenue.net
SpecificMEDIA, Inc.
Third Screen Media
Tremor Network
Tribal Fusion
Undertone Networks
Vizi Media
Winstar Interactive Media