" Posthumanist" theories have become increasingly popular among scholars in political ecology and other fields in the human sciences. The hope is that they will improve our grasp of relations between humans and various nonhumans and, in the process, offer the means to recompose the" social" and the" natural" domains. In this paper, I assess the merits of posthumanisms for critical scholarship. Looking specifically at the work of Bruno Latour (including his latest book, An inquiry into modes of existence) and Donna Haraway, I argue that posthumanist thinking offers not only analytical but normative advantages over conventional and even Marxian approaches. But these newer frameworks contain their own ethico-political limitations and, to the extent that they are useful for addressing conditions of injustice, they continue to depend upon conceptual resources from their precursors. For this reason, a critical political ecology would best be served by preserving a tension between humanist and posthumanist methods.