This book examines anti-spam measures in terms of their potentials, limitations, advantages, and drawbacks. These factors determine to which extent the measures can contribute to the reduction of spam in the long run. It examines legislative, organizational, behavioral, and technological anti-spam measures. In addition, it presents the conceptual development and analysis of an infrastructural e-mail framework, which features such a complementary application. After the presentation of the technological and organizational facets, the framework is analyzed twofold: its theoretical effectiveness is assessed with the aid of the formal model mentioned above and its storage and traffic requirements are analyzed quantitatively. The author further considers deployment issues, as the framework would have to be integrated in both the technological and the organizational Internet infrastructure.