The implementation of livestock-based circularity strategies contributes to creating healthy and sustainable territories thanks to the: (1) reduction of environmental impacts through synergies in nutrient and energy flows, soil carbon storage in grasslands, organic matter recycling, the transformation of non-edible biomass in food, etc.; and (2) socioeconomic development and food security by the creation of wealth and jobs. Despite the recognition of the place of livestock in sustainable development, actors seem to be sparsely or poorly equipped with tools to identify potential and to co-design circular economy projects adapted to their territories. The main scientific objective of the CLiMiT project is to develop and test a toolbox to support actors in the construction of livestock-based circularity projects considering territorial specificities and actors' preferences. Our project adopts a research-intervention approach with a transformative goal. We place the circularity paradigm as the primary vector of territorial development compatible with a reduction in greenhouse gas emissions. We propose an interdisciplinary and comprehensive 3-step approach: (1) characterizing the socio-ecological functioning of territories to better understand them; (2) modelling the different biomass and nutrient flows to assess the environmental and socio-economic impacts of the territories; (3) co-design with local stakeholders technical and organizational solutions for the implementation of circular economy projects including livestock farming.