Following the social conception of moral agency, this paper claims that many beings commonly exempted from moral responsibility, like young children, adults with late-stage dementia, and nonhuman animals, may nevertheless qualify as participants in moral responsibility practices. Blame and other moral responsibility responses are understood according to the communicative emotion account of the reactive attitudes. To blame someone means having an emotion episode that acts as a vehicle for conveying a particular moral content. Therefore, moral agency is argued to be (...) manifested in communicative exchanges between a claimant and a defendant. While many human and nonhuman agents are justifiably exempted from ascriptions of moral responsibility, this does not necessarily exclude such agents from the community of moral agents altogether. Toddlers and dogs, for instance, seem capable of other-directed reactive attitudes, like resentment, and could, therefore, qualify as participants in moral responsibility practices with respect to the claimant position. Therefore, we may have reason to adopt a distinct claimant-directed participant stance to some beings, even if they fail to qualify as apt targets of blame. This expanded theoretical room for moral agency is argued to make explicit further normative considerations. (shrink)