In contrast to recent political, scholarly, and public misuse of the term, this essay articulates a more accurate definition of the hostage concept. This definition is not only consistent with a broad range of etymological sources, but is also in agreement with numerous examples from the historical and anthropological record. A possible application of the hostage idea to mid/late-twentieth-century superpower relationships, involving a distinctively different approach to nuclear deterrence, is also described. Attention is further called to the fact that the giving of hostages as confidence-building “emissaries of trust” incorporates several attributes that might be of interest to contemporary evolutionary theorists. A closer examination of the biological and behavioral underpinnings, the historical and anthropological precedents, and the political and psychological efficacy of this ancient idea might therefore prove to be a fruitful area for future empirical and theoretical research.