While a number of significant campaigns since the early 1990s have resulted in bans of particular weapons, at least as many equivalent systems have gone unscrutinized and uncondemned by transnational campaigners+ How can this variation be explained? Focusing on the issue area of arms control advocacy, this article argues that an important influence on the advocacy agenda within transnational networks is the decision-making process not of norm entrepreneurs nor of states but of highly connected organizations within a given network+ The argument is illustrated through a comparison between existing norms against landmines and blinding laser weapons, and the absence of serious current consideration of such norms against depleted uranium and autonomous weapons+ Thus, the process of organizational issue selection within nongovernmental organizations~NGOs! and international organizations~IOs! most central to particular advocacy networks, rather than the existence of transnational networks around an issue per se, should be a closer focus of attention for scholars interested in norm creation in world politics+ A number of transnational advocacy campaigns have emerged in recent years bent on regulating or banning certain weapons: landmines, cluster munitions, and small arms to name a few+ These campaigns have had notable effects on international norm-making by governments+ 1 But at least as many equivalent systems have gone uncondemned by such transnational networks+ For example, thermobaric weapons fuel-air explosives!, which create fireballs over large areas and kill through suffocation and burning, have been likened to nuclear weapons in their immediate I gratefully acknowledge Kenneth Anderson, Michael Barnett, Clifford Bob, Lynn Eden, James Fearon, Brooke Greene, Don Hubert, Robert Keohane, Alex Montgomery, Kenneth Rutherford, Richard Price, and Jack Snyder for helpful suggestions as this project developed; Jim Ron, Stuart Shulman, and Richard Rogers for synergistic conversations about the study of human security networks; the director and staff of the Qualitative Data Analysis Program lab at UMass-Amherst; the engagement by graduate students associated with my Human and Social Dynamics grant and course on Global Agenda-Setting at University of Massachusetts-Amherst; and the assistance of all the human security practitioners and norm entrepreneurs who lent their time to speaking with me as part of this project+ 1+ For example, the landmines and cluster munitions campaigns have resulted in binding treaty bans; while the small arms campaign has not yet succeeded in norm development, a process is underway within global policy networks+ and indiscriminate effects, yet have not been condemned by humanitarian law organizations+ 2 Psychotropic weapons such as cognitive enhancers or mood-altering aerosols might fall under the chemical weapons regime and have been criticized by a small but vocal network of U+S+ and Russia-based activists, but these weapons have largely been overlooked by mainstream arms-control networ...