In 2001, the international community pushed to conclude a monitoring protocol for the Biological and Toxin Weapons Convention (BWC). This 1972 treaty, which bans the development, testing, production, storage, and use of germ weapons, lacks provisions to verify compliance with its prohibitions. Monitoring the Biological and Toxin Weapons Convention is an extremely difficult task because nature is the source of the microorganisms that are the basis of biological weapons, and scientists often examine these microorganisms to study diseases. Moreover, technical advances have allowed governments to clean a facility’s pipelines in minutes thereby giving a government the ability to cheat. As a result, the BWC protocol negotiators would need to stretch the horizons of monitoring technologies and strategies if they were to succeed in creating a meaningful and feasible protocol. The Stimson Center’s Chemical and Biological Weapons Nonproliferation Project turned to nongovernmental technical expertise to explore the technical challenges associated with monitoring compliance with the BWC. The Stimson Center recruited experts from research institutes and universities, pharmaceutical and biotechnology companies, and defense contracting firms. The Stimson Center asked these groups to brainstorm the technical aspects of BWC monitoring. A fourth group was composed of inspection veterans. Chapter 1 of the report explains how the brainstorming sessions were conducted and chapter 2 summarizes the lifespan of the BWC, including the major developments in the efforts to strengthen the treaty. Chapters 3 and 4 present in full the monitoring tools and strategies that the academic and industry brainstorming groups proposed for use in their respective settings. Insights from defense contractors and inspection veterans are reported throughout the report. The report’s final chapter highlights the similarities and differences between the draft BWC provisions and the ideas that emerged during the independent discussions of the four brainstorming groups.