Espionage or spying is the act of obtaining secret or confidential information from non-disclosed sources or divulging of the same without the permission of the holder of the information. A person who commits espionage is called an espionage agent or spy. Any individual or spy ring (a cooperating group of spies), in the service of a government, company or independent operation, can commit espionage. The practice is clandestine, as it is by definition unwelcome. In some circumstances, it may be a legal tool of law enforcement and in others, it may be illegal and punishable by law.