Paul Murphy , Has an post titled CIO Taxonomy, and goes on to list according to him what the most common seterotypes of CIO's are, excerpts of the same:

1. Bluffer. Bluffing is the easiest and most common CIO survival strategy. This generally works well for many people because it leverages the simplistic assumptions senior executives usually make about systems to retain credibility with them and then uses their imprimatur to shield the CIO from direct criticism.

2."Tweetie nerd". This type of CIO spends his time meeting with people outside both his own systems group and the internal chain of command while muttering darkly about external threats and loudly asserting his support for user oriented desktop services. In reality, however, he depends on a few main applications that run on a single Unix or OS/400 machine somewhere and keeps most desktops at least a full generation behind the market.

3. A variant on greenmail, works pretty well too. These CIOs get the job and disappear into their offices never to be heard from again until eventually senior management is forced into action, or the company changes hands, and they collect on their severance package before moving to the next target.

4. Absent genius. This CIO dispenses brilliant business and technical advice to all comers - except those in his own company. He speaks at conferences, creates coalitions, explores options, and sits on standards bodies while presenting private dreams as done deeds and blinding senior management in the glare of who he knows, and who he speaks of, to the fact that the systems organization is winding down behind him on auto pilot.

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Prashanth Rai