Ethnography has consistently faced ethical questions since the earliest postmodern critiques of the ethnographer's claims to objectivity in descriptive research. Concerns of how to represent ethically the ethnographic Other, to engage in activist research, and to foster collaboration among researchers and participants persist even in the age of critical ethnography and its strict attention to these issues. This article offers activity theory as a useful tool with which to address the ethical and practical difficulties that continue to plague critical ethnographers. I argue that by seeing the project of ethnographic research as an activity system as described by A. N. Leontiev and expanded upon in the work of David Russell and Yrjo Engestrom, researchers can recognize the shifting locus of expertise between researcher and participant and thus design a research project that is more ethical and, ultimately, more useful for all involved. Ultimately, activity theory serves as a means of helping ethnographers recognize the actual nature of what they are doing when they conduct research so that they may confront ethical challenges in a more fully theorized fashion. (Contains 10 notes.)