4) CTO = Chief IT R&D Officer Applicable to all businesses where technology is not the main product or service, this version of the CTO has the most limited scope. They are responsible for knowing about relevant technologies, possibly running experiments, defining technology standards for the company and managing relationships with sources of insight and innovation, such as universities and analyst firms.
5) CTO = Über-Architect Here the CTO is responsible for the governance of key technology decisions, technical architecture decisions and setting of standards. It may extend beyond technical architecture to the whole of enterprise architecture (EA). This role would typically be interchangeable with a chief architect title.
6) CTO = Head of the Office of the CIO This CTO heads up the office of the CIO. They are not responsible for the core run-the-business or grow-and-transform the business IT, just the transversal functions, which typically includes architecture, governance, IT finance, IT HR, IT procurement, IT risk and security, and, possibly, the running of the IT project and program management office.The most important thing is that, if the term "CTO" is used in your business, it is clear to all internal and external stakeholders what it means in your business.
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