CIO or cio may refer to:

Organizations Governmental organizations Central Imagery Office, an office of the US Department of Defense that was a predecessor of the National Geospatial-Intelligence Agency Central Intelligence Office, the national intelligence agency of the former South Vietnam Central Intelligence Organisation, the national intelligence agency of Zimbabwe Corruption Investigation Office for High-ranking Officials, a government agency of South Korea

Non-governmental organizations , a Mexican research centre in optics Charitable incorporated organisation, a form of legal entity for non-profit organizations in the United Kingdom or International Olympic Committee, an international sports federation Congress of Industrial Organizations or Committee of Industrial Organization, a 1935–1955 national trade union centre that merged into the AFL-CIO Credit and Investments Ombudsman, an Australian dispute resolution service

Titles Chairperson-in-office, an official of a member state holding the presidency of an international organization Commonwealth Chairperson-in-Office, an official of the Commonwealth of Nations Chief information officer, the head of information technology Chief innovation officer, the head of innovation, responsible for innovation management Chief investment officer, the head of investments

Other uses CIO (magazine), both print and online Concurrent input/output, a feature in the JFS file system Conventional International Origin, a conventionally defined reference axis of the pole's average location "Cry it out", an aspect of the Ferber method for solving childhood sleep problems City One station, Hong Kong, MTR station code

See also