SSI

SSI may refer to:

Companies

• Sahaviriya Steel Industries, Thai steel company
• Samsung Semiconductor Inc., a Korean electronics company
• Space Services Inc., a team of companies investigating new commercial opportunities in space
• Strategic Simulations Inc, computer gaming company that produced war and simulation games from the mid-1980s to late 1990s.
• Survey Sampling International, a global provider of sampling solutions in marketing research program
• SSI Group, a healthcare revenue cycle company; see Rosa Lavín

Science and technology

• Soil-structure interaction, the interaction between soil and structures (e.g. buildings), especially in seismic engineering
• Solid State Interlocking, the brand name of a railway signalling system developed in the 1980s in the UK
• Solid state ionics, the study of ionic-electronic and ionic conductors (solid electrolytes) and their uses
• SteadyShot Inside, a sensor-based camera image stabilization system by Sony

Computing

• Serializable snapshot isolation, a way to allow multiple concurrent transactions to see consistent information when making changes to a database
• Server Side Includes, a server-side scripting language used on the Web
• Self-sovereign identity, the user has a means of generating and controlling unique identifiers as well as some facility to store identity data.
• Shared Source Initiative, a source-available software licensing scheme by Microsoft
• Simple Sensor Interface protocol, a simple communications protocol designed for smart sensors
• Single sign-in, a specialized form of software authentication
• Single system image, a cluster dedicated operating system
• Small-scale integration, a type of integrated circuit
• Synchronous Serial Interface, a serial interface standard for industrial applications

Medicine

• Stress–strain index, a measure of bone strength
• Surgical site infection
• Sliding scale insulin, fast- or rapid-acting insulin only given subcutaneously

Economics and government

• Standing settlement instructions, payment processing and settlement information about financial institutions
• Strategic sustainable investing, an investment strategy that recognizes financial value in transitional leadership towards sustainability
• Supplemental Security Income, a United States federal government program
• Scottish statutory instrument, a form of secondary or subordinate legislation in Scotland
• Sensitive security information, a category of sensitive information under the US government's information sharing and control rules

Military and police

• Selective Service Initiative, a form of military conscription in the United States
• Senior station inspector, a rank in the Singapore Police Force
• Shoulder sleeve insignia, formation insignia used by the United States Army
• Soldier Support Institute, a U.S. Army organization
• Staff Sergeant Instructor, an appointment in the British Army
• State Security Investigations Service, former Egyptian agency
• Strategic Studies Institute, the US Army War College institute for geostrategic and national security research and analysis
• Attack Submarine (Diesel Air-Independent Propulsion) (hull classification symbol: SSI), a submarine classification type used by the US Navy
• Subsecretaria de Inteligência, the Brazilian intelligence agency until 1995

Organizations

• Sano Sansar Initiative, a global youth organization
• Scuba Schools International, a diver training organization
• Software Sustainability Institute, a UK-based, academic software organisation
• Space Science Institute, an American nonprofit organisation based in Boulder, Colorado
• Space Studies Institute, an American non-profit organization based in Mojave, California
• Spastics Society of India, former name of Able Disable All People Together
• Spatial Sciences Institute, a professional body in the Asia-Pacific region
• Statens Serum Institut, the Danish State Serum Institute
• Swedish Radiation Safety Authority (Statens strålskyddsinstitut), a Stockholm-based regulatory and research government agency
• Students Supporting Israel, a network of pro-Israel student organizations in North America and the United Kingdom
• Swedish Society for Interlingua, a society that encourages the active use of Interlingua in Sweden

Other uses

• Socio-scientific issues, controversial social issues which relate to science
• Solid State Ionics, a peer-reviewed scientific journal
• Solid State Intelligence, a malevolent entity described by John C. Lilly
• St. Simons Island, a barrier island on the coast of Georgia, US
• Star of the Solomon Islands, the most senior award made by the government of the Solomon Islands
• Sustainable Society Index, a tool for assessing the sustainability of 151 assessed countries