Technological solutions for tracking raw material flows in complex supply chains (RIA) There is a need to improve supply chain data transparency and traceability, enabling consumers and downstream producers to have information about the origins of metals in finished products. In order to achieve the expected outcomes, it is advised to involve industrial users from the downstream side. Due diligence has numerous research gaps in this area which need to be addressed in order to limit complexity and enable a level playing field for responsible sourcing of minerals.This action should close those gaps by the setting up of technological solutions for tracking raw material flows (material passports), building upon comparable criteria, reporting and audit approaches. Examples would include transparency in payments and traceability from beginning to end of the supply chain, through a chain of custody certiﬁcation, and the use of block chain technology in an eﬀort to improve supply chain transparency and traceability.The action should build on the experience of existing EU projects on international responsible sourcing and contribute to strengthening responsible sourcing agenda.It is foreseen that this will facilitate responsible sourcing in complex supply chains and put companies downstream in the supply chain in a better position to inﬂuence companies upstream.The proposal should build on the state of the art in sustainable raw materials traceability with regard to sustainability certification schemes, standards and initiatives as well as block chain technology. The proposal should also build on the experience from earlier Horizon 2020 projects in the area of responsible sourcing of raw materials in global value chains. The proposal should cover CRMs in at least five complex supply chains, including a batteries value chain.The action should also contribute to improving the awareness of relevant external stakeholders and the general public across the EU about the importance of raw materials for society and of the challenges related to their sustainable supply.In this topic the integration of the gender dimension (sex and gender analysis) in research and innovation content is not a mandatory requirement.