This cross-sectoral learning brief distils the in-depth reports and tools from the M3 Partnership that can be found on the M3 Partnership website or ISEAL website. This brief also reflects on the recommendations from the earlier 2018 research, testing and expanding on the recommendations made at the start of the M3 Partnership. This brief is meant to leverage the learnings from the multi-year collaboration of the M3 Partnership organisations and inspire sustainability systems working in other sectors.