'''CIU''' may refer to: *Crash Investigation Unit, an Australian factual television program *Working Men's Club and Institute Union, an association of social clubs in the United Kingdom *Chippewa County International Airport in Sault Ste. Marie, Michigan (IATA Code: CIU) *Columbia International University, a Bible college and seminary in Columbia, South Carolina *Cyprus International University, Cyprus, North Cyprus *Cape plc, a construction company listed in the Alternative Investment Market under ticker CIU * Customs and Immigration Union (Canada) * Chronic idiopathic urticaria, also known as '''hives''' * Collective investment undertaking, another term for an investment fund * Conviction Integrity Unit, a division of a prosecutorial office, working to prevent, identify, and remedy false convictions *Cédula de Identidad de Uruguay, the Uruguayan identity card *Convergència i Unió, a Catalan political party {{disambig}}