Sustainable animal breeding should ensure efficient resource use and animal health and welfare, while preserving genetic diversity. The EU-funded GEroNIMO project will provide new knowledge and tools to promote innovative genome- and epigenome-enabled selection methods for traits related to production efficiency, productive longevity, fertility, resilience and welfare. The initiative will build on current knowledge, analysing chicken and pig populations to quantify the contribution of genetic and epigenetic variation in gene expression, trait variation and trade-offs between traits. Researchers will characterise breeds phenotypically, genetically and epigenetically under different environments to identify underlying biological mechanisms affecting trait variation. They will also develop techniques for improving selection by integrating genetic and non-genetic factors and strategies for conserving genetic and epigenetic diversity.