ISE

• International Society of Electrochemistry, a global scientific society founded in 1949
• Islamic Society of Engineers, principlist political organization of engineers in Iran

Education

• Iceland School of Energy, a school jointly owned by Reykjavik Energy, Reykjavik University, and Iceland GeoSurvey
• Institute for Shipboard Education, administrator of the Semester at Sea study-abroad program
• Institute for Social Ecology, an educational institution in Plainfield, Vermont
• International School Eindhoven, an international school in the northern part of Eindhoven, Netherlands
• International Student Exchange, Ontario, a non-profit organization allowing students to participate in reciprocal student exchange programs

Stock exchanges

• International Securities Exchange, a United States stock exchange
• Irish Stock Exchange, Ireland's main stock exchange
• Islamabad Stock Exchange, now Pakistan Stock Exchange
• Istanbul Stock Exchange, a former Turkish stock exchange that merged and became Borsa Istanbul

• Fraunhofer Institute for Solar Energy Systems (Fraunhofer ISE), an institute of the Fraunhofer Society
• Information Sharing Environment, a United States government program
• Initiative for Science in Europe, an independent platform of European learned societies and scientific organisations
• ISE Corporation, a company that developed hybrid electric drivetrains for heavy-duty transportation
• Ion selective electrode, a transducer that converts the activity of a specific ion dissolved in a solution into an electrical potential
• Xilinx ISE, software for synthesis and analysis of hardware description language designs
• Integrated Scripting Environment (Windows PowerShell)