Résumé : After the technical feasibility of the decentralized user support was demonstrated earlier, this study phase elaborated on questions with respect to the sharing of responsibilities and how to operate the different types of payloads. After having worked out an appropriate classification for payloads it is shown that a clear scheme about the distribution of responsibilities during the various phases of an experiment has been found and that the payload operation can be performed in the vicinity of the researcher. The aspect of development support has been picked up by the user support to minimize the development process. A list of the tasks to be performed in support of the development of experiments has been compiled with a detailed description for each payload class. © 1993.