CONTEXT: European farms and regions follow the trend of agricultural specialisation, which results in a disconnection between crop and livestock production. High-input specialised farming systems are continuing to be developed even though they generate negative environmental impacts. Despite these trends, a few pioneering farmers have intentionally reintegrated livestock onto crop farms in several regions. To date, research has rarely examined farmers’ motivations to develop such systems. OBJECTIVE: We aimed to identify French farmers’ motivations for reintegrating livestock onto specialised crop farms and into crop-producing regions. METHODS: Following innovation-tracking principles, we identified 18 crop farmers who had reintegrated livestock in two regions where crop farming predominates: Occitanie and the Parisian Basin. The farmers’ profiles varied in production mode, farm size, the crops and livestock produced, and the type and duration of livestock reintegration. Semi-directed interviews focused on the farmers’ motivations for having reintegrated livestock. At the end of the interviews, we asked them to select and rank 10 of 36 cards that represented their main agronomic, economic, social and environmental motivations for crop-livestock farming. We transcribed the interviews and performed inductive content analysis, which was then triangulated with the farmers’ rankings of the cards. RESULTS AND CONCLUSIONS: Seven categories of motivations for reintegrating livestock emerged from the interviews: following personal ethical and moral values, increasing and stabilising income, promoting ecosystem services, increasing self-sufficiency and traceability, connecting to the local community, decreasing pollution and keeping the landscape open. In both discourse analysis and motivation card rankings, agronomic motivations (including promoting ecosystem services) were predominant, especially improving soil life and fertility. Farmers ranked economic and social categories nearly equally. Improving and stabilising income was cited by 17/18 farmers in their discourse, consistently with the two most-selected economic motivation cards. Strengthening social connections was the most-selected social motivation in card rankings and was mentioned by 14/18 farmers in their discourse, particularly for connections among farmers. Environmental motivation cards were selected less often, except for environmental stewardship, which was consistent with the desire to build an environmentally friendly farming system to follow personal ethical and moral values mentioned by 10 farmers in their discourse. SIGNIFICANCE: This study is the first to provide a ranked summary of crop farmers’ motivations for reintegrating livestock. Understanding this diversity is an initial step in incentivising, promoting and/or supporting the development of this innovative sustainable practice under favourable conditions and can encourage public actions that promote it.