The Circular Economy (CE) is built on the principle of closing resource loops and keeping products and materials in use for as long as possible, in contrast to the Linear Economy, which relies on extracting resources from the environment and their subsequent disposal. This shift is vital for sustainable development and achieving climate neutrality by 2050. The agro-industrial sector significantly impacts both the economy and environment, requiring effective strategies for waste and by-product valorization. Material Flow Analysis (MFA) provides a structured methodology to assess the flows and stocks of materials within a system over a defined period and a specific spatial boundary. By mapping the movement of materials across the supply chain’s links, MFA enables the identification of inefficiencies, waste generation points, and potential areas for circular resource use. As such, it serves as a key analytical tool for evaluating resource efficiency and supporting the transition to a CE.

This study applies MFA to the oliviculture and poultry sectors in the Centro Region of Portugal, to quantify material flows, identify hotspots of waste and by-product generation, explore valorization opportunities, and offer practical recommendations to facilitate CE transition. Data collection will involve semi-structured interviews with key stakeholders and surveys distributed to relevant regional companies, with additional data from national and international databases. Findings will offer insights applicable to other agro-industrial sectors and regions, reinforcing the value of MFA as a key decision-making tool for identifying critical waste generation points, exploring by-product and waste valorization opportunities and enhancing resources circularity.