Hospital pharmacists are involved in clinical trials for the management of experimental drugs. In our hospital, the pharmacy is in charge of approximately 120 clinical trials and this activity is sub-divided between three sectors. The fragmentation of this activity generates difficulties in terms of heterogeneity of practices, redundancy of activities, and difficulties of communication with stakeholders outside the pharmacy due to the multiplicity of pharmaceutical interlocutors. The aims of this work were to improve and harmonize practices, and to reorganize and globalize the activities carried out in this sector.A Lean management approach was employed. The process was mapped and then a double analysis was conducted. On the one hand, wastes and irritating were identified collaboratively, at project group meetings. On the other hand, a reorganization model was proposed.A diagnosis with 38 points to improve was drawn. The reorganization applied to human resources, by reducing the number of actors involved in a rational way, and secondly, tasks were revised and harmonized.The use of a lean methodology allowed us to perform successfully our reorganization. This approach led to continuous improvement in a collaborative manner in this sector.