In the context of alliances, mergers & acquisitions and divestitures of activities we propose an integrated approach to the strategy, to the organization and to the management based on an information system which on the one hand provides the actors with tools for change and on the other hand is the object of the change. First we give an overview of the mutation process and we briefly expose the principles and concepts we retain for an integrated approach to strategy, organisation and management in the context of mutations. Then we go all over the phases of the process to present how the procedures we identified in the context of alliances, mergers & acquisitions and divestitures of activities are supported by an information system which supports the decision and favors the creativity of the actors. Third, from the priniciples and concepts we retain, we create a meta—model that is the heart of the information system. It provides tools for designing changing situations of configurations of activities and permits to federate the thoughts of strategy, organization and management.