The IP telephony Cookbook is divided into chapters, which guide the reader through increasing levels of knowledge of the IP telephony world. This first chapter contains introductory information and details the contents of the Cookbook, as well as useful tips on how to read this document and techno-economic considerations. Chapter 2 explains the technology background needed in order to understand the topics addressed in the rest of the Cookbook; in this chapter the basic IP telephony components are described and an overview of the IP telephony protocols is given. Chapter 2 ends with additional considerations on call routing and perspectives about the future. Chapter 3 gives a high level overview of scenarios a user may face when building an IP telephony environment, while details are given in order to explain what a particular scenario is about, what is needed in order to deploy it and what needs it is serving. The next three chapters (Chapter 4, Chapter 5 and Chapter 6) detail how to set up IP telephony services; those chapters give the reader the chance to learn how to set up basic services, advanced services (still telephony centric) and value added services (with respect to the classic telephony service). Chapter 7 is about Global telephony integration, describing the technology solutions available for global IP telephony integration and successful replacement of classic telephony. Moreover, Chapter 7 reports on today's situation, as well as migration and future trends. The last chapter contains regulatory/legal considerations users have to be aware of when moving from classic telephony to IP telephony. The topics here relate to the regulation of IP telephony in Europe and in other countries out of the EU. A large number of classic telephony legal issues will be detailed (from Licensing to Unbundling) and their mapping to the IP world. Finally, the IP telephony Cookbook contains two annexes: Annex A and Annex B. While Annex A is focused on list and describing briefly the current and future IP telephony Projects in Europe to learn from, Annex B gives the reader useful information about IP telephony hardware and software, reporting "hands on" experience (i.e., how the devices performed, how good tech-support was, what were the workarounds for some of the problems faced, etc).