The Outdoor Advertising Association of America Slide Library spans the years 1891 through the 2000s, with the bulk of the collection originating in the 1950s and later. The collection documents over a hundred years of outdoor advertising primarily in the United States, plus some international campaigns from several other continents. The Slide Library is a large collection, almost entirely comprised of slides of billboards, exhibiting a grand range of graphic artistry, advertising campaigns, and marketing strategies. A smaller group of images supports the ad collection with views of artwork, billboard construction and other related images. In addition to over 62,000 slides, there are a few early glass slides, as well as transparencies, a small number of paper files, and six audiocassettes accompanying slide presentations. Many images were submitted by outdoor advertising companies over a number of years to the Outdoor Advertising Association of America (OAAA) as entries in annual national competitions to determine the best poster designs. The OAAA currently sponsors the OBIE Awards, which were preceded by awards programs under various names and sponsorships starting in the early 1930s. The award is modeled after the ancient Egyptian obelisk, considered by many the earliest form of outdoor advertising. Indeed much of the collection can be seen as evidence of this awards program although only the Award Nominees Series contains slides labeled as such. Other slides probably were transferred to OAAA when companies cleaned out their back files, though the precise sources of many items are unknown. The slides were maintained at OAAA primarily as a large supply of creative examples for member companies. Researchers interested in the following subjects may find the Outdoor Advertising Association of America Slide Library especially helpful: the outdoor advertising medium itself, advertising awards, advertising design, billboard construction, and commercial art, as well as the many outdoor advertising companies, advertisers, and advertising campaigns represented.