HarWASTing aims to develop innovative business models based on circular economy (CE) principles to promote bioeconomy in rural areas, by implementing a set of scalable and replicable technological solutions to efficiently exploit underutilised biomass from forestry and agriculture to develop innovative and high-value products. These models will support sustainable management practices and will promote an efficient use of natural resources, reducing overall waste generation and post-harvest losses by implementing valorisation processes and fostering CE principles. To this end, a methodology will be implemented to collect, treat and revalorize biomass from forest and agricultural harvest, pruning waste and bioethanol process side-streams, respecting the cascade principle for biomass use. A one-fits-all technology, Hydrothermal Carbonization, for a higher energy efficient treatment of lignocellulosic biomass residues will be combined with Pressurized Hot Water Extraction and innovative post-treatment technologies, to develop high-value added products and avoid any non-valorised side-stream. The whole concept will be demonstrated at small-scale pilot, built-upon existing wood, food and bioenergy value chains to further strengthen their economic and environmental sustainability through synergistic interlinkages between them. Mediterranean, Boreal and Continental bioregions will be studied. The holistic concept is based on the central valorisation route of Hydrothermal Carbonizationand its solid product, hydrochar, that is converted into hybrid wood-hydrochar panels with less than 10% of bio-adhesive for special applications such as fire protection or electromagnetic shielding. A novel support AI-based digital tool for forecasting agroforest feedstock availability will be developed. Innovative digital passports will help to commercialize the panels and bioadhesives. The hydrochar will be offered on a new digital platform which also serves for networking and for publishing of best-practices.