Book excerpt: This book presents the most interesting talks given at ISSE 2005 - the forum for the interdisciplinary discussion of how to adequately secure electronic business processes. The topics include: Corporate Governance and why security implies to control the enterprise - Risk Management and how to quantify security threats - Secure Computing and how it will change the way we trust computers - Digital Rights Management and the protection of corporate information. Adequate information security is one of the basic requirements of all electronic business processes. It is crucial for effective solutions that the possibilities offered by security technology can be integrated with the commercial requirements of the applications. The reader may expect state-of-the-art: best papers of the Conference ISSE 2005.