Stone & Webster was an American engineering services company based in Stoughton, Massachusetts. It was founded as an electrical testing lab and consulting firm by electrical engineers Charles A. Stone and Edwin S. Webster in 1889. In the early 20th century, Stone & Webster was known for operating streetcar systems in many cities across the United States including Dallas, Houston and Seattle. The company grew to provide engineering, construction, environmental, and plant operation and maintenance services, and it has long been involved in power generation projects, starting with hydroelectric plants of the late 19th-century; and with most American nuclear power plants.

CB&I, previously Chicago Bridge & Iron Co, was a large engineering, procurement and construction (EPC) company with its administrative headquarters in The Woodlands, Texas. CB&I specialized in projects for oil and gas companies, and once employed over 32,000 people worldwide. In May 2018 the company merged into McDermott International. McDermott struggled to integrate its acquisition of CB&I. On January 21, 2020, McDermott announced that it had filed for Chapter 11 bankruptcy due to asbestos litigation. A $22.5 million trust fund was made to handle asbestos claims.