Addressing agro-industrial waste managementWaste management is an urgent challenge that requires innovative and sustainable strategies to protect the environment, safeguard public health and enable efficient resource recoveryResource recovery in the agricultural sector. A promising approach is to convert waste into bio-based fertilisersBio-based fertilisers that can be marketed and applied to soils as sustainable alternatives to both mineral and organic conventional fertilisers. These alternative fertilisers can improve agricultural productivity and quality, strengthen supply security and reduce reliance on traditional commercial chemical fertilisers, thereby increasing the sector’s strategic resilience. In this context, it is worth noting the EU project I3-4-BIOFERTILIZERS, which aims to establish new European value chains for bio-based fertilisersBio-based fertilisers by promoting interregional collaboration and investing in circular economy innovations. This project focuses on accelerating the adoption of sustainable innovations and expanding both the production and market availability of bio-based fertilisersBio-based fertilisers. A key investment case within the project focuses on transforming chicken manureChicken manure into compost, emphasising a recycling strategy with significant agronomic value. Chicken manureChicken manure can also be co-managed with other agro-industrial waste to enhance value and final product features. In line with this, this chapter explores the engineering, environmental and health aspects of valorising agro-industrial residues, focusing on transforming chicken manureChicken manure into safe compost for sustainable fertiliser production. This approach is fully aligned with Sustainable DevelopmentSustainable development GoalsSustainable Development Goals (SDGs) 2, 6, 12 and 13.