# PSA

PSA, PsA, Psa, or psa may refer to:

## Biology and medicine

* Posterior spinal artery
* Primary systemic amyloidosis, a disease caused by the accumulation of abnormal proteins
* Prostate-specific antigen, an enzyme used as a blood tracer for prostate cancer
* Psoriatic arthritis, an inflammatory disease
* Pseudomonas aeruginosa, a species of bacterium
* Pseudomonas syringae pv. actinidiae, a pathovar of a bacterium that attacks kiwifruit

## Chemistry

* Polar surface area, the surface sum over all polar atoms of a molecule
* Pressure swing adsorption, a technology for separating, or purifying, gases

## Computing

* Professional services automation, software for automating project and billing management for professional service firms
* PSA Certified, Platform Security Architecture, a security certification for the Internet of Things
* Plesk Server Administrator, a commercial web hosting automation program
* Persistent staging area, a staging area in data vault modeling

## Contracts, legislation, and government

* Passenger Vessel Services Act of 1886 or Passenger Services Act, US
* Payment Services Act, Singapore
* Primary statistical area, a collective term for metropolitan, micropolitan, and combined statistical areas
* Problem-solution approach, an approach for assessing inventive step at the European Patent Office
* Production sharing agreement, a contract between a government and a resource extraction company
* Public Safety Act, a law in Jammu and Kashmir
* Public service agreement, UK government department targets for 3-year period
* Public service announcement
* Purchase and sale agreement, an agreement between a buyer and a seller

## Organizations
### World-wide scope

* Pacific Science Association
* Pacific Sociological Association
* Philosophy of Science Association
* Pro Snowboarders Association
* Professional Skaters Association
* Professional Squash Association

### Specific to large English-speaking countries

* Australia:
** Pharmaceutical Society of Australia
** Public Schools Association, Perth
** Public Service Association of NSW, a trade union
** The Salvation Army, Parramatta
* United Kingdom:
** Phone-paid Services Authority
** Political Studies Association, for academics
** Professional Standards Authority for Health and Social Care
** Property Services Agency, former government agency
* United States:
** Partnership for a Secure America
** Photographic Society of America
** Pi Sigma Alpha, college honor society for political science
** Poultry Science Association

### Other country-specific organizations

* Parti Solidaire Africain (Democratic Republic of the Congo), defunct political party
* New Zealand Public Service Association, trade union
* PSA BPOL a specialised police unit within the Federal Police of Germany
* Petroleum Safety Authority Norway, governmental supervisory authority
* Palestinian Scout Association
* Philippine Statistics Authority
* Philippine Support Association, raising credit for the poor
* Polish Society of Actuaries
* PSA International (Singapore), formerly Port of Singapore Authority
* Public Servants Association of South Africa, trade union
* Partido Socialista de Andalucía (Spain), former name of the Andalusian Party
* Socialist Party of Aragon (Partido Socialista de Aragón), a now defunct Spanish political party
* Authentic Socialist Party (Argentina), Partido Socialista Auténtico
* Public Services Association (Trinidad and Tobago), a trade union
* Partido Socialista Argentino, the Argentine Socialist Party, a now merged Argentinian political party

## Transport

* PSA Airlines, a subsidiary of American Airlines Group
* Pisa International Airport, Pisa, Italy, IATA code PSA
* Pacific Southwest Airlines, US, 1949 to 1988, ICAO code PSA
* Penn Station Access, a planned New York City rail upgrade
* PSA Group, Peugeot Société Anonyme, a defunct French multinational automobile manufacturer now part of Stellantis

## Other uses

* "PSA" (song) by SZA, from the album Lana (2023)
* PSA 5.7 Rock, a pistol
* Penal substitutionary atonement, a theory of atonement in Christianity
* Professional Sports Authenticator (PSA), an authenticator of sports and trading cards, and similarly hand-signed artifacts
* Autonomous Socialist Party (disambiguation)
* Pisa language or Asue Awyu, ISO 639-3 code psa
* Piscis Austrinus (Southern Fish) constellation, IAU abbreviation PsA
* Public Storage stock ticker
* Power Station of Art, a contemporary art museum in Shanghai, China
* Pressure-sensitive adhesive
* "PSA", title of an earlier version of the R.E.M. song "Bad Day"
* Palmetto State Armory, an American firearms company based in Columbia, South Carolina.