The Southwestern Bell Building is a 28-story, 121.0 m skyscraper constructed to be the headquarters of Southwestern Bell Telephone in downtown St. Louis, Missouri. At the time of its construction it was Missouri's tallest building. The building, which was one of the first in St. Louis to use setbacks, has 17 individual roofs. Its architect was Mauran, Russell & Crowell, who also designed the Federal Reserve Bank of St Louis and the Railway Exchange Building (St. Louis). I.R. Timlin, Southwestern Bell's company architect, was associate architect on the project.