Prof Caelli is the Head of the School of Software Engineering and Data Communications at the Queensland University of Technology (QUT), Brisbane, Queensland, Australia. He co-leads the cyber law and policy research group in the Information Security Research Centre (ISRC) at QUT, a research centre of which he was the Founding Director in 1988. He has 40 years of experience in the IT industry, with some 28 years involvement in information security and cryptography. He founded ERACOM Pty Ltd in 1979, a company that develops and markets advanced, integrated cryptographic systems and information security products around the world, having started with the creation of high performance micro-computer systems based upon the Stanford University Network (SUN) workstation architecture. He worked with both Hewlett-Packard and Control Data Corporation in the 1970s.

He is a Fellow of the Australian Computer Society and the Institute for Combinatorics as well as being a Senior Member of the IEEE. In 2002 he was presented with the Kristian Beckman Award by Technical Committee 11 of IFIP for his international work in information security and received the Pearcey Medal in September 2002 for his lifelong work in the IT industry. He was made an Officer in the Order of Australia (AO) in the January 2003 Australia Day honours list.