The goal of our research is to characterize practices shared in an online community dedicated to ergonomics in order to understand how these online discussions are a means to construct co-elaborated knowledge about ergonomics and its practices. This communication presents a preliminary study of the nature (purpose of interactions, topics) and structure (relations between participants, purposes and topics) of exchanges on Ergoliste, a French speaking online mailing list dedicated to ergonomics. We show that the mailing list is mostly dominated by ergonomists (consultants, ergonomists working in private companies, institutions, students) seeking and sharing resources: information about jobs and resources (documentation, literature, etc.) and experiences about various topics (methodology, trades of ergonomics, specific tools or work settings...). It also opens some prospects for more longitudinal investigations of the contents of the list, to analyze more deeply how the list can be viewed as an efficient tool to co-elaborate knowledge about ergonomics and its development.