| Acronym | Definition |
|---|
| SIS | sister |
| SIS | Student Information Systems |
| SIS | State Information Service (Egypt) |
| SIS | Students in Service (est. 1997) |
| SIS | Secret Intelligence Service (MI6) |
| SIS | Success in Soccer (magazine; various locations) |
| SIS | School of Information Sciences |
| SIS | Science in Sport (nutrition) |
| SIS | School of International Service (American University, Washington, DC) |
| SIS | Silence Is Sexy |
| SIS | Success in Stages (bullying intervention program) |
| SIS | Say It Straight (Texas) |
| SIS | Summer in Switzerland |
| SIS | Semester in Spain (various schools) |
| SIS | Siemens IT Solutions |
| SIS | Stand-in-Stead |
| SIS | Single-Instance Storage |
| SIS | Superannuation Industry (Supervision) Act (Australia) |
| SIS | Specialty Insurance Services (Paoli, PA) |
| SIS | Stay-In-School (program) |
| SIS | Schengen Information System |
| SIS | Services Information System (North Carolina) |
| SIS | Safety Instrumented System |
| SIS | School of International Studies |
| SIS | Shivas Irons Society (golf; Carmel, CA) |
| SIS | Scientific Instrument Services (Ringoes, NJ) |
| SIS | School of Indigenous Studies (Australia) |
| SIS | Second-Impact Syndrome (brain injury) |
| SIS | School of Information Systems (Singapore) |
| SIS | Secure Information Sharing |
| SIS | Sundaram Infotech Solutions (India) |
| SIS | Singapore Indoor Stadium (est. 1989) |
| SIS | Super Image Stabilizer |
| SIS | School Internet Server |
| SIS | System Integrity Services |
| SIS | Single Ink System |
| SIS | Single Image Stereograms |
| SIS | Stateful Inspection System |
| SIS | Silicon Integrated Systems |
| SIS | Specialized Information Services |
| SIS | Software Integration Services |
| SIS | Student Information System |
| SIS | Startup Info Structure |
| SIS | Scalable Internet Services |
| SIS | System Installation Suite |
| SIS | Satellite Informations Service |
| SIS | Supplier Information System |
| SIS | Statistical Information System |
| SIS | Secure Internet Services |
| SIS | Systems Integrators |
| SIS | Single Instance Store |
| SIS | Services Information System |
| SIS | Specialized Information Services (National Library of Medicine) |
| SIS | Single Instance Store (Microsoft Windows 2000) |
| SIS | Seisen International School (Tokyo, Japan) |
| SIS | Strategic Infrastructure Security (computer training) |
| SIS | Special Information Systems (US DoD) |
| SIS | Standardiseringen I Sverige |
| SIS | Small Intestinal Submucosa |
| SIS | Schlumberger Information Solutions |
| SIS | Smaller Island States |
| SIS | Simple Instruction Set |
| SIS | Silicon Integrated System(s) |
| SIS | Spatial Information System |
| SIS | Servicio de Inteligencia Naval (Italian: Naval Intelligence Service) |
| SIS | Six-Item Screener (cognitive impairment) |
| SIS | Stroke Impact Scale |
| SIS | Strategic Intermodal System |
| SIS | Strategic Information System |
| SIS | SegainterSettle AG (Swiss Central Securities Depository) |
| SIS | School of Information Studies |
| SIS | Social Inclusion Strategy |
| SIS | Shop in Shop (various companies) |
| SIS | State Institute of Statistics |
| SIS | Signal-in-Space (L1 or L2 signal transmitted from GPS satellites to GPS receivers) |
| SIS | Suspended Imposition of Sentence (legal) |
| SIS | Stuff I've Seen (Microsoft search team, Ottawa, Canada) |
| SIS | Swarm Intelligence Symposium (IEEE) |
| SIS | Share Incentive Scheme |
| SIS | Single Image Stereogram |
| SIS | Sequential Importance Sampling |
| SIS | Software Interface Specification |
| SIS | Special Investigations Section |
| SIS | Superconductor/Insulator/Superconductor |
| SIS | Shift-Invariant Space (mathematics) |
| SIS | Security Information Systems |
| SIS | Student Intervention Services (various schools) |
| SIS | Society for Interdisciplinary Studies |
| SIS | Symbian Installation System (mobile phones) |
| SIS | Studijni Informacni System (Czech: Student Information System) |
| SIS | Science Information Strategy (Natural Environment Research Council; UK) |
| SIS | Seoul International School |
| SIS | Susceptible Infected Susceptible |
| SIS | Siemens Industrial Services (Canada) |
| SIS | Safe Injection Site (various locations) |
| SIS | Special Investigation Squad (TV show) |
| SIS | Side Impact Sensor (automobiles) |
| SIS | Standardiseringskommissionen I Sverige |
| SIS | Species Impact Statement (environmental conservation) |
| SIS | Shimano Index System |
| SIS | Senior Intelligence Service |
| SIS | Serotonin Irritation Syndrome |
| SIS | International Workshop on Secure Information Systems (IEEE Workshop) |
| SIS | Shekou International School (China) |
| SIS | Simulator Interface System (US NASA) |
| SIS | Slovak Information Service |
| SIS | Satellite Instrument Shelter |
| SIS | Scientific Instrument Society |
| SIS | Safety Injection System |
| SIS | Software Intensive System |
| SIS | Special Interest Seminar (various organizations) |
| SIS | Streamlined Inspection System |
| SIS | Software Implementation Specification |
| SIS | Semiconductor Insulator Semiconductor |
| SIS | Schwerionensynchrotron (Gesellschaft für Schwerionenforschung mbH) |
| SIS | Seiko Instruments Singapore (est. 1973) |
| SIS | Senologic International Society |
| SIS | System Infrastructure Software |
| SIS | Sections Internationales de Sèvres (French bilingual school) |
| SIS | Standalone Identification System (aerospace) |
| SIS | School of Intercultural Studies (Fuller Theological Seminary, Pasadena California) |
| SIS | Standard Interface Specification |
| SIS | Soccer Information Systems |
| SIS | Styrene Isoprene Styrene Block Copolymer |
| SIS | Shipbuilding Innovation Scheme (Australia) |
| SIS | Swedish Institute for Standards (central body for standardization) |
| SIS | Schwab Investor Services |
| SIS | Special Information System |
| SIS | Space Information Systems |
| SIS | Serviços de Informação e Segurança |
| SIS | Safety Interlock Switch |
| SIS | Social Indicators Survey |
| SIS | Spacecraft Interface Simulator |
| SIS | Simple Image Service |
| SIS | Slope Information System (Hong Kong) |
| SIS | Siteseeing Internet Services (Netherlands) |
| SIS | Sound In Syncs |
| SIS | State Intermodal System (Florida, USA) |
| SIS | Stiftung für Internationale Solidarität und Partnerschaft |
| SIS | Space and Intelligence Systems |
| SIS | Sigurnosno Izvestajna Sluzba (Security and Information Service, Croatia) |
| SIS | Skier Insurance Services |
| SIS | Saline Infused Sonogram |
| SIS | Standard Information System |
| SIS | Space Inventory System |
| SIS | System Integration and Support |
| SIS | Stepwise Isothermal Segregation |
| SIS | Standard Indexing System |
| SIS | Système Information Sociale |
| SIS | Stroudsburg Intermediate School |
| SIS | Space Intelligence Squadron |
| SIS | Southern Information Systems, Inc. |
| SIS | Signalling Interworking Subsystem |
| SIS | SCI Isolation Segment |
| SIS | Scanning Imaging Spectrometer |
| SIS | Saman Information Structure (Iran) |
| SIS | Sensor Image Simulator |
| SIS | Superconducting Image Surface |
| SIS | Signatured Instruction Stream |
| SIS | Servicios Israelis de Seguridad (Guatemalan security firm) |
| SIS | Simposio de Ingeniería de Software |
| SIS | Simple Internet Solutions |
| SIS | Synopsis Information System (DCAA) |
| SIS | Selective Inquiry System |
| SIS | Satellite Intercept System |
| SIS | Strategic Intelligence Summary |
| SIS | Surface-ionization-type Ion Source |
| SIS | Site Integrated Schedule |
| SIS | Single Interceptor Satellite |
| SIS | Simulation Induced Sickness (program) |
| SIS | Sistemas Israelitas de Seguridad (Guatemala) |
| SIS | Slovenský Internetový Spravodaj (Slovak Internet Search) |
| SIS | Stil I Stål (Finnish: Style in Steel) |
| SIS | Subversive Intellectual Society |
| SIS | Solar Interplanetary Satellite |
| SIS | Sales Implementation Specialist (Sprint) |
| SIS | Statistical Inventory Sampling |
| SIS | Shuttle Interface Subsystem (US NASA) |
| SIS | Slovenská Informacná Služba (Slovak Information Service) |
| SIS | Station Indépendante Satellite (Belgian radio) |
| SIS | Supply Information System |
| SIS | Saratoga Investama Sedaya (Indonesia) |
| SIS | Special Inventory System |
| SIS | Special Isotope Separation/Separator |
| SIS | Serial Interface Server |
| SIS | Standardized Interface Specification |
| SIS | Single Image Software |
| SIS | Sensor & Instrumentation System |
| SIS | Scientific Information Services Limited (St. Augustine, Trinidad & Tobago) |
| SIS | Simulator Interface Subsystem |
| SIS | Switch Interface System |
| SIS | Surface Instrumentation Subsystem |
| SIS | Special Intelligence Study |
| SIS | Secondary Items Study |
| SIS | System Integrity Statement |
| SIS | Sensory Index Score |
| SIS | Server Infrastructure Strategy |
| SIS | Ship's Information System |
| SIS | Standard Inspection Sheet |
| SIS | Site Information Set |
| SIS | Shock Inertia Switch |
| SIS | Stow Infrastructure System |
| SIS | Status Interrupt Signal |
| SIS | Supervisory Investigative Specialist |
