CES

CES may stand for:
 * Closed ecological system, isolated from the outside
 * Clean Energy Standards
 * Constant elasticity of substitution, in economics, a feature of a particular class of production function
 * The ISO 639 code for the Czech language

Technology

 * Consumer Electronics Show, annual trade show, Las Vegas, Nevada, US
 * Circuit Emulation Service, a telecommunication technology
 * Cryogenic energy storage
 * Character encoding scheme, a reversible transformation of sequences of code units to sequences of bytes
 * Charge-exchange spectroscopy, a diagnostic used in plasma physics

Companies

 * ICAO Code designator for China Eastern Airlines

Medicine

 * Cauda equina syndrome, a serious neurological condition
 * Cranial electrotherapy stimulation, therapeutic brain stimulation
 * Camurati-Engelmann disease, also called "Camurati Engelmann syndrome" (CES)
 * Carboxylesterase, an enzyme that catalyzes the reaction between a carboxylic ester and water

Organization

 * Caspian Engineers Society
 * Center for Economic Studies, University of Munich
 * Center for Ethical Solutions, bioethics think tank in the United States
 * Centre for Environmental Studies, former UK research organization
 * Church Educational System, of The Church of Jesus Christ of Latter-day Saints
 * Coalition for Economic Survival, a Los Angeles–based community organization
 * Coalition of Essential Schools, US educational reform
 * Community Exchange System, international Internet trading network
 * Commonwealth Employment Service, former Australian Government employment agency
 * Confédération Européenne de Scoutisme or Confederation of European Scouts
 * Centre for European Studies (disambiguation), the name of several educational institutions
 * Center for Election Science, a US-based Approval voting advocacy organization

People

 * Jean Ces, French boxer of the 1920s

Transportation

 * Central South station, a proposed MTR station in Hong Kong
 * Cessnock Airport, IATA airport code "CES"