Chief information officer (CIO), chief digital information officer (CDIO) or information technology (IT) director, is a job title commonly given to the most senior executive in an enterprise who works with information technology and computer systems, in order to support enterprise goals.

Normally, the CIO reports directly to the chief executive officer, but may also report to the chief operating officer or chief financial officer. In military organizations, the CIO reports to the commanding officer. The role of chief information officer was first defined in 1981 by William R. Synnott, former senior vice president of the Bank of Boston, and William H. Gruber, a former professor at the Massachusetts Institute of Technology Sloan School of Management. A CIO will sometimes serve as a member of the board of directors.