A few books include components of the architecture, design, theory, problems, challenges, and recommended policies for IM security, but none of them address issues in IM in ways that are useful for the daily operation and management of enterprise networks. UNIQUE FEATURES / RATIONALE There are no recent book that includes components of the architecture, design, theory, problems, challenges, and recommended policies for IM security. No book that we know the address of the IM security in a way that is useful for daily operation and management of IM-capable networks in the corporate environment today.