Harley Ellis Devereaux is an architecture and engineering firm based in Southfield, Michigan with offices in Southfield, Chicago, Illinois, Los Angeles, San Diego and San Francisco, California. The firm was founded in 1908 by architects Alvin E. Harley and Norman S. Atcheson. As of 2008, Harley Ellis Devereaux is one of the 150 largest design firms in the United States, employing more than 250 professionals including programmers; architects; civil, mechanical, electrical, and structural engineers; landscape architects; interior designers; graphics, signage, and equipment designers; and construction specialists. The firm specializes in multiple practices including health care, life enhancement, science and technology, corporate and commercial, mixed use and residential, K-12 schools, higher education, civic and cultural and industrial and automotive. Harley Ellis Devereaux has also designed most of the Archdiocese of Detroit buildings that have been built since 1970.