In the competitive mattress-making industry, Serta sleeps with one eye open. The company is one of the nation's top mattress producers, but has seen rival Tempur Sealy leapfrog it in industry rankings. Serta asserts that it's also one of the world's top manufacturers of mattresses. To its benefit, Serta supplies hotels and motels, such as Hilton and Waldorf, with its products. Its Perfect Sleeper line is the nation's best-selling premium mattress; its top-of-the-line collection sells under the Perfect Day name. Founded in 1931, Serta boasts nearly 30 manufacturing facilities in North America. Serta is controlled by the private equity firm Advent International.