This chapter proposes a supplementary metric to that of representation. It argues that whether a group should enfranchise those that affiliate to it depends on whether they also happen to be the constituency the group advocates for. Groups that advocate for non-human constituencies cannot enfranchise their constituency, so enfranchising the affiliates of such groups is not necessary for democratic legitimacy. The chapter identifies a framework for identifying those interest groups that are, in principle, capable of representation, and those of solidarity. It also demonstrates why the solidarity/representation distinction is not simply repeating other binary distinctions already in the literature.