The chapters of this volume are grouped into a number of topical areas demonstrating that the security canon is a very varied one. As Chris Earnshaw so rightly highlighted in his preface, getting the appropriate security built into new products, systems and services is fundamental to a rosy Internet future. We highlight a number of the vital issues to address as part of that process.

Chapter 1 reminds us of the importance of securing the infrastructure. Only when this has been done can the applications which run on it be deployed with any confidence from a security perspective.

The next two chapters introduce functionality which is starting to play an important part in the application security story. XML, the next-generation of HTML, is now viewed as the standard way information will be exchanged in environments that do not share common platforms. Special purpose XML languages and standards are practically announced daily. Chapter 2 describes XML digital signatures and XML encryption, while Chapter 3 explains how these can be used to provide Web-based security services.

An even newer idea is SecML, the Security Modelling Language. As systems become more complex, so the task of designing an appropriate security model becomes ever more challenging. Chapter 4 introduces a new approach which may help in this task.

XML will be an increasingly important technology underpinning public key infrastructures (PKIs). Chapter 5 tells us what else is new in this area. Chapter 6 shows us how both XML and PKI can be used...