R.D. Folsom has joined the law offices of Robert C. McCandless.

Thomas P. Genis has been appointed manager of business development for the architectural firm of Delon Hampton & Associates. He was most recently senior project manager at the Washington office of Bernard Johnson Inc.

Roderic Muir Frederickson has been named a partner with the accounting and consulting firm Coopers & Lybrand. He was formerly a director with the firm.

John S. Pachter has become a partner with the law firm of Wickwire, Gavin & Gibbs. He was formerly with McKenna, Conner & Cuneo.

Edward C. Stephan Jr. has been named a regional sales director with the computer services company Dilacom Inc. He was formerly an IBM account manager.

James W. Fay and John R. Glennie have been elected vice presidents with Robert R. Nathan Associates Inc. Fay succeeds retiring senior vice president Robert H. Johnson as director of international business operations. Both Fay and Glennie previously held other positions with the firm.

James J. Greeves has been named a principal and partner with the management consulting firm of Theodore Barry & Associates.

James G. Lowenstein and Michael E. Sterner have been named as managing directors with International Relations Consultants Inc. Lowenstein is a former U.S. Ambassador to Luxembourg and Sterner is a former U.S. Ambassador to the United Arab Emirates.

Raymond A. Lenhardt has been named a participating principal with Arthur Andersen & Co. Thomas M. Aiello, James A. Meriwether and Michael A. Stein haved been named partners with the firm.

Martin B. Danziger has joined the law firm of Barst, Mukamal & Babitt as a partner and head of the firm's Washington office.

Frederick R. Dunham has joined Maryland Switch Inc. in Baltimore as president. He was formerly a vice president with Maryland National Bank.

Henry A. Anderson has established Anderson Consulting Services Inc. He was formerly with the 3M Company.

Robert L. Plouffe has been named executive vice president of government information systems for Planning Research Corp. He was previously president of the systems division of Computer Sciences Corp.