CIS

• CIS (mathematics)
• CIS Corps (Ireland)
• CIS Tower
• CIS national football team
• Calcutta International School
• Canadian Ice Service
• Canadian Identification Society
• Canadian International School Vietnam
• Canadian International School of Sanya
• Canadian Interuniversity Sport
• Cancer Information Service
• Canton Island Airport
• Carcinoma in situ
• Card information structure
• Case Information Statement
• Cayman International School
• Cebu International School
• Center for Immigration Studies
• Center for Internet Security
• Center for Internet and Society (disambiguation)
• Centre for Independent Studies
• Chinese International School
• Christians in Science
• Cis (disambiguation)
• Cisalpino
• Clifford International School
• Clinically isolated syndrome
• Co-operative Insurance Society
• College in the Schools
• Colombo International School
• Combined intracavernous injection and stimulation test
• Common Intelligibility Scale
• Commonwealth Police
• Commonwealth of Independent States
• Communities In Schools
• Community Innovation Survey
• Comodo Internet Security
• CompuServe Information Service
• Computer information system
• Confederacy of Independent Systems
• Configuration interaction singles
• Contact image sensor
• Continuous Injection System
• Continuous ink system
• Copenhagen International School
• Copper indium selenide
• Corpus Inscriptionum Semiticarum
• MIT Center for International Studies
• United States Citizenship and Immigration Services