When Irish immigrant Timothy McCarthy started building farmhouses and barns in Ann Arbor, Mich., in 1864, he had no idea that, 150 years later, his firm, McCarthy Holdings Inc. (No. 18), would be a multibillion-dollar national enterprise.
There have been numerous milestones in the company's history. For example, McCarthy self-performed the complex concrete work on the parabolic arches of the Priory Chapel in St. Louis in 1961, establishing its reputation for working on tough projects.