Marine and coastal ecosystems have been severely degraded due to human activities, as even local activities can have large environmental impacts due to ecosystem connectivity and compounding effects. Hence there is a growing effort to rebuild and repair ecosystems, but there is often a mismatch in the spatial scale of repair. Scaling up nature repair to match impacts can be achieved by not only increasing the extent of area repaired, but also by maximizing outcomes per unit area. In this talk, I will review how the effects of local activities, whether positive or negative, can transcend realms and compound at regional, national and even global scales. Drawing from research on tidal wetlands and oyster reefs, I will explore how nature repair activities can have large positive effects that transcend the area being repaired. I highlight that harnessing ecosystem processes and understanding the sources of uncertainty are key to maximising repair outcomes.