RSA may refer to:
Organizations
Academia and education
- Rabbinical Seminary of America, a yeshiva in New York City
- Regional Science Association International (formerly the Regional Science Association), a US-based learned society
- Renaissance Society of America, a scholarly organization based in New York City
- Rhetoric Society of America, an academic organization for the study of rhetoric
- Royal Scottish Academy, a Scottish art institute
- The Royal Society of Arts, formally the Royal Society for the encouragement of Arts, Manufactures and Commerce, a British institution
Military
- Redstone Arsenal, a United States Army post adjacent to Huntsville, Alabama
- Royal New Zealand Returned and Services' Association, an organization for the welfare of veterans of New Zealand's military
- Royal School of Artillery, a training establishment for artillery warfare in the British Army
- Royal Signals Association, an organization for serving and retired members of the Royal Corps of Signals
Other organizations
- RSA Insurance Group, UK
- RSA Security, a US network security company
- Rehabilitation Services Administration, a US Department of Education agency
- Retirement Systems of Alabama, US
- Ridley Scott Associates, a UK film company
- Road Safety Authority, Ireland
- Russian Ski Association
Places
- Republic of South Africa
- Santa Rosa Airport (Argentina), in La Pampa province (IATA code RSA)
In science and technology
Cryptography and security
- RSA (cryptosystem) (Rivest-Shamir-Adleman), for public-key encryption
- RSA Conference, annual
- RSA Factoring Challenge, for factoring a set of semi-prime numbers
- RSA numbers, with two prime numbers as factors
Biology, organic chemistry, and medicine
- Rsa RNA, partially characterised non-coding RNA from Staphylococcus aureus
- Respiratory sinus arrhythmia, the heart rate variation due to respiration
- Retrosynthetic analysis, in organic chemistry
Other uses in science and technology
- RSA (missile), a Swiss-developed surface-to-air missile system
- Rational Software Architect, part of IBM Rational Application Developer
- Real-time Spectrum Analyzer, spectrum analyzer with no blind time
- Remote supervisor adapter an out-of-band management interface on IBM servers
- Residual stress analysis, the study of the influence of residual stress on a material's mechanical properties
- Revolver Stechkina-Avraamova, a designation of the Russian OTs-01 Kobalt revolver
- Roentgen stereophotogrammetric analysis, also called radiostereometric analysis, a method of calculating 3D orientation using X-ray images
Other uses
- Ray Steadman-Allen, a composer of music
- Responsible Service of Alcohol, alcohol server training in several Australian states
- Revenu de solidarité active, a French in-work welfare benefit
- New Hampshire Revised Statutes Annotated, an entire body of laws
- Runway safety area or runway end safety area
- Repressive state apparatuses, a concept in Louis Althusser's philosophy