Several studies stressed that the introduction of CPOE applications deteriorates the doctor-nurse communication. But there are many factors that might influence communication behaviors, as for example the way these communications are organized. The present study aims at showing that the impact of a CPOE system on the cooperative activities can be controlled given that a good understanding of the cooperative workflows support the implementation. By analyzing the doctors-nurses communications during the medication use process, the study demonstrates that the technical system has no impact on the cooperative activities within a given organization. CPOE does not induce differences in the dialogs' durations and contents.