SMI may refer to:
Business Service Measurement Index, for IT services Swiss Market Index, of the stock market
Companies SensoMotoric Instruments, provider of eye tracking hard- and software Shepardson Microsystems, Atari 8-bit and Apple II software company SMI, brand of Silicon Motion ICs Speedway Motorsports (formerly Speedway Motorsports, Inc.), owner and operator of auto racing racetracks and related companies Shanghai Municipal Investment Group, China Sony Music India, Hindi music and film production company owned by Sony Music Entertainment
Computing .smi, file extension for SAMI files Scalable Memory Interconnect interface in Intel Xeon E7 processors .smi, self mounting image file extension Structure of Management Information, in SNMP .smi, file extension for Synchronized Multimedia Integration Language SMI, system management interrupt for System Management Mode Serial Management Interface, to configure an Ethernet PHY
Physics Vertico SMI or Vertico Spatially Modulated Illumination, a fast microscope
Medical Serious mental illness
Other uses Sergeant major instructor in the British Army Shape Modeling International, annual scientific symposium Social media intelligence Sports Management International, a fictional sports agency in the film Jerry Maguire St. Michael's Institution, a school in Malaysia Samos International Airport, Greece, IATA code Storage Management Initiative - Specification (SMI-S), a data storage standard Support for Mortgage Interest, a UK welfare benefit Sustainable Minerals Institute, a research institute at the University of Queensland, Australia