"Building confidence in outer space activities" sets out to clarify some of the prerequisites and modalities of a confidence-building process in outer space. More precisely, it is the result of efforts undertaken by several experts on outer space matters who examine the role of Earth-to-space monitoring in: enhancing the safety of outer space activities, and preventing the deployment of weapons in that environment. In this context, the experts efforts are particularly intended to address the political, technical, and economic dimensions of Earth-to-space monitoring. However, their ultimate objective is to ascertain the extent to which the different existing CSBMs proposals are politically and technologically possible as well as financially viable. After such an evaluation, the book concludes by proposing the creation of an International Earth-to-Space Monitoring Network (ESMON) as the most appropriate means to improve both transparency and predictability in outer space activities.