Researchers and trialists working on NPIs need to share results and cross data. However, no solutions has been designed to this aim. Ontology is a wildly used way to represent complex information and interrelationships. It is shared and linked to other existing resources available on the Web of Data (Linked Open Data) with the use of the socalled URI [1]. We aim to define a shared ontology of NPIs which will be considered as an open source reference when dealing with NPIs (research and clinical practice). The vocabulary must include the list of all terms related to NPIs and their relations (e.g., synonymy, generalization). Methods: Building an ontology is a complex task that requires a considerable amount of human effort. We consider a collaborative approach that allows all researchers to edit/update/add the concepts related to NPIs, including categories, terms and relations in the form of an ontology. For this purpose, we consider the use of existing tools that must be extended and connected. There are some tools which are used from huge number of people such as WebProtégé [2], BioPortal [3], Swoop, Apollo, OntoStudio [4]. We look for tools that meet the following criteria. Conclusions: The shared ontology is being built. The first results are promising but show how difficult it is to define a shared vocabulary. We claim that this will be a solid and important step to the CEPS Platform (Montpellier, France). It will then allow to improve data retrieval and data crossing for better understanding NPIs and better defining advanced digital tools.