This paper makes some suggestions for a concept of community which arguably satisfies the most important criteria for both human communities, as defined in the social sciences and humanities, and natural communities, as defined in ecology and biology. Beginning with the former, I arrive at two such criteria: (1) a material and social connection among members, and (2) some kind and degree of awareness of other members. These are then supplemented with a third drawn from civic republicanism, with its focus on citizenship and the common good: communities (3) enable and require certain practices for their maintainence. Turning to ecological definitions of community, I find the dominant (reductionist) one seriously deficient as compared with a more holist and ecosystemic approach. However, I invoke a nonreductive holism to defend the idea of community, and go on to argue that each of the three above-mentioned criteria can be fruitfully extended to include both social and ecological communities in a nonreductionist way - that is, in a way that neither reduces ecosystemic properties to individual organisms nor the reverse. This culminates in a discussion of what I call 'ecological republicanism', which I suggest could have powerfully positive effects on the contemporary crisis of undue human impact on the natural world.
