The National Security Agency has a set of official responsibilities.
National Security Agency . The NSA is responsible for global monitoring , collection , and processing of information and data for foreign intelligence and counterintelligence purposes , a discipline known as signals intelligence ( SIGINT ) . As part of these streamlining responsibilities , the agency has a co-located organization called the Central Security Service ( CSS ) , which was created to facilitate cooperation between NSA and other U.S. military cryptanalysis components .