The aim of the present article is to propose a new approach to improve interactions between stakeholders, using traceability and contractualization. Faced with a crisis generated by volatility, collective action, incorporating all stakeholders, including consumers, is needed: but what exactly must be done? The article first describes the SDSC approach which combines three main concepts: Extended Demand, Extended Supply and Demand-Supply Chain (DSC), and then goes on to detail how a collaborativemodeling tool needs to be built up.