SIP

Places

Safety improvement plan, a plan for improving safety
Sales incentive plan, a type of employee incentive program
Securities information processor, the part of public infrastructure for disseminating market data in the United States
Share Incentive Plan, a UK government approved employee plan
Systematic investment plan, an investment strategy

Session Initiation Protocol (SIP), a communications protocol for signaling and controlling multimedia communication sessions, including voice over IP

Service Improvement Plan, a former program to provide a defined level of basic telephone service to all Canadians
Standard Interchange Protocol, in library systems
System Information Packet, in the DMX512 standard for stage lighting control
Session Initiation Protocol, a signaling protocol most commonly used in Internet Telephony

SIP (software), a tool which generates C++ interface code for the programming language Python
Scilab Image Processing, an image processing toolbox
Soft Input Panel, on-screen input method for devices without standard keyboards
Submission Information Packages, in the Open Archival Information System Reference Model; see Open Archival Information System#The OAIS environment and information model
System Integrity Protection, a security feature of OS X El Capitan by Apple

Semiconductor intellectual property, a business model for licensing intellectual property
Single in-line package, for packaging electronic components
System in package, chip technology, also known as a chip stack multi-chip module
Silicon photonics, silicon semiconductor used as an optical medium

Social information processing, an activity through which collective human actions organize knowledge
Supplementary Ideographic Plane, a range of ideographic characters in the Unicode standard
Stochastic Information Packet, an array of simulation realizations

Second-order intercept point, a measure of linearity in amplifiers and mixers
Shelter Implementation Plan, will help contain and manage the consequences of the Chernobyl disaster
Signature image processing, in welding fault detection
Sputter ion pump, a type of vacuum pump
Standard inspection procedure, a process for checking compliance
Sterilization-in-place, in sanitation of food preparation equipment
Structural insulated panel, a composite building material

SIP Animation, originally Saban International Paris, France based TV production company
Société genevoise d'instruments physiques, Swiss manufacturer of precision machinery
Société Immobilière Publique, a state-owned housing company in Burundi
Società Italiana per l'Esercizio Telefonico (originally Società Idroelettrica Piemontese), the former name of Telecom Italia
Selznick International Pictures, a defunct film studio
SIP Strojna Industrija, Slovenian agricultural machinery manufacturer

Semi-infinite programming, a type of mathematical optimization problem
Spectral induced polarisation, in geophysics
Stable-isotope probing, used in molecular biology
Statistically improbable phrases, a system used to find unique phrases for use as keywords
Stochastic Information Packet, in probability management, a representation of the probability distribution of a variable
Strongly implicit procedure, an algorithm for solving a sparse linear system of equations
Structure-inducing probes, a peptide synthesis to stabilize long peptides

"Sip", a song from Joeboy
Stranka Ivana Pernara, a Croatian political party
Shelter-in-place, an emergency procedure
Sip (kinship)
Sip or Zip, one of the 18 months of the Haab', a part of the Maya calendric system
SIP Grenade, self igniting phosphorus
The Society of International Photographers, a not-for-profit organization founded in 1936
Soviet Interview Project, a research project conducted in the early 1980s
Strangers in Paradise, an award-winning comic book
State Implementation Plan, a United States state plan for complying with the federal Clean Air Act
Sub-irrigated planter, a type of gardening container
Sip as in SipSipStefan
"Sip", a 2017 song by Chris Brown from Heartbreak on a Full Moon