A complete collection of Roger Clemens baseball cards would cover a lot of card history. When trading cards were first printed, they were used to advertise different products. Some types of companies that made cards include bakery, tobacco, caramel, ice cream, periodicals, and gum of course. Cracker Jacks sometimes offered small baseball cards as the included prize. Baseball cards became a product in their own right instead of just a means of advertising.

In modern baseball card history, Bowman was the major producer of cards until 1956 when Topps bought the company and controlled the market for many years. Some other companies tried to gain a foothold. Fleer signed an exclusive contract with Ted Williams and produced a set of cards devoted to him. Topps and Fleer both sold gum with their cards. Topps stopped most of its competition by using its licensing agreements to force other companies from producing cards. In 1981, however, both Fleer and Donruss made baseball cards. Topps sued them both but lost when the court ruled that its exclusive agreement with the major leagues only extended to cards sold with gum. That is why there are three Roger Clemens baseball cards in his rookie year. Other companies also joined in saturating the market. Competition improved card quality and novelties like holograms. Between companies going bankrupt and selling out to larger companies, the market finally was trimmed down to just Topps and Upper Deck