Plastics are strategic materials for several key sectors and the rethinking of plastics within the circular economy concept is pivotal for a more sustainable and resource efficient Europe. In particular, composites and thermosets, materials of choice for applications where long-term use and mechanical resistance are critical, cannot be mechanically re-processed since at elevated temperature they do not flow but degrade. A powerful new strategy to produce reprocessable cross-linked polymers is the functionalization of the polymer matrix with cross-links able to reverse or exchange at elevated temperatures. These covalent adaptable networks (CANs), also known as vitrimers, are able to shuffle chemical bonds through exchange reactions at high temperature, allowing for material reprocessing. To fully exploit the potential of vitrimers in high-end consumer goods, their properties need to be tailored to the specific application by embedding functional additives. Moreover, to accomplish vitrimer circularisation, such properties must also be preserved upon recycling. The VIT proposal intends to engineer vitrimers by endowing these polymers with highly desired functional optical and electrical properties, which are retained after recycling, fulfilling the circular economy paradigm “use-reuse-repair-recycle”. The VIT network gathers the expertise required to tackle this timely challenge. The consortium is composed of 10 high-level academic research groups from 3 different continents (Europe, America, Asia) and 2 highly innovative companies. By the seconding of 97 ERs/ERSs across Europe and worldwide, the aim is to capitalize on the consortium expertise in the chemistry and processing of functional materials to develop a new generation of advanced functional vitrimers able to satisfy the stringent requirements of reprocessability while preserving their properties.