Qlarion of Arlington named Jake Bittner president and chief executive.
Ruppert Landscape of Laytonsville named Bill Cobb, former branch manager for Environmental Design Group, information systems manager.
Citizant of Chantilly named Frank Nigro, former operations manager, division director.
CACI International of Arlington named Gregory Scovel, former acting director of the Naval Criminal Investigative Service, vice president of the cyber law enforcement and force protection division in the cyber solutions group. He will be based in Chantilly.
Carana of Arlington named Santiago Sedaca president.
Ridge Global of the District named Jocelyn Gamble, former director of business development at Global Security and Engineering Solutions, director of client management.
CTLGroup of the District named Steven J. Smith officer and co-leader of the buildings and facilities practice group.
Aronson & Co. of Rockville named Jeffery P. Capron managing officer.
PricewaterhouseCoopers of the District named Kimberly K. Peretti director in its U.S. forensic technology solution practice.
Apco Worldwide of the District named Timothy P. Cost, former senior vice president for corporate affairs at Wyeth, global chairman for health care and executive vice president.
TeleCommunication Systems of Annapolis named Allen Green vice president strategic programs for government.
Biologics Consulting Group of Alexandria named Craig A. Halverson, former vice president of regulatory affairs and quality assurance at SciClone Pharmaceuticals, senior consultant.