The study of the role and evolution of the information technology function in organizations has prompted much interest among researchers in our field for some time now. Many researchers have tried to describe the IT function and to explain its transformation over time. However, we have observed that the existing typologies are often based on a single dimension, attached to historical periods, or built into a normative discourse that calls for an ideal archetype of the IT function. Rather than following these views, we propose that there exist many archetypes of IT functions, and that each one of them evolves in response to a limited number of parameters. First, based on a literature review, we propose a typology of the roles of the IT functions within archetypes that are defined according to four fundamental dimensions. Second, we apply this typology in an examination of the process by which IT functions are transformed over time, helped in this by the punctuated equilibrium theory. The ultimate objective of this paper is to provide a new conceptual and theoretical perspective on the role played by IT functions in organizations and on how such functions may evolve or transform over time.