Founded as Adams Engineering in 1946, Adams & Clark, Inc. is a full service, interdisciplinary consulting firm of 35. Dan Clark became a principal in 1978. Stuart Deysenroth and Leslie Killingsworth joined as principals in 1985. Adams & Clark is headquartered in Spokane, Washington, with a branch office in Post Falls, Idaho. We have performed professional consulting services for private and public clients throughout the western portions of the United States and Canada.