The BioTheRoS project aims to develop cost-effective and sustainable value chains for biofuels production by advancing two key thermochemical conversion technologies, i.e. pyrolysis and the upgrading of its intermediate products, and gasification and Fischer-Tropsch (FT) synthesis, to TRL5. Although these technologies are technically distinct, they are jointly investigated through a multidisciplinary approach, encompassing: (i) feedstock selection, (ii) pilot-scale testing, (iii) scale-up modeling, (iv) integration with renewable hydrogen and Carbon Capture Utilization, and (v) comprehensive life cycle assessments addressing environmental sustainability, socio-economic impact, and economic viability. To support decision-making, BioTheRoS will employ AI-driven predictive models using GIS data and aligned with EU biofuel policies. These tools are designed to forecast biomass demand, mitigate risks, enhance cost-efficiency, and inform the development of innovative business models. The project will also assess the competitiveness of pyrolysis and gasification fuels relative to other renewable alternatives, such as electrification and biofuels, in hard-to-decarbonize sectors, including heavy-duty transport, aviation, and shipping. At the same time, it will develop scale-up strategies based on advanced modeling techniques and pilot-scale demonstrations. Furthermore, BioTheRoS will identify and quantify concrete measures to improve the environmental, social, and economic sustainability of thermochemical biomass conversion processes. This includes evaluating the impact of technology improvements and integration strategies on overall system performance and sustainability indicators. Finally, BioTheRoS will foster international collaboration and stakeholder engagement to enhance global knowledge and accelerate the development of sustainable advanced biofuel value chains. This will be achieved via shared research, aligned EU and global initiatives, and a dedicated knowledge-exchange network.