The following is what the IIA website says about the CIA :
The CIA designation is the only globally accepted certification for internal auditors and remains the standard by which individuals demonstrate their competency and professionalism in the internal auditing field. Since the program’s launch in1973, it has opened up countless doors of opportunity for practitioners around the world as it communicates their ability to serve as a key player in their organization’s success. Candidates leave the program enriched with educational experience, applicable knowledge, and business tools that can deliver a positive impact in any organization or business environment.