In the beginning of 2003, I found a short article about the privacy implications of RFID technology in a newspaper. It raised my interest, and after reading some early research papers on the topic, I thought: "There must exist better solutions. " I c- cerned myself with the topic in my spare time. After having developed my rst - lutions, I asked my supervisor, Prof. Dr. Paul Muller ], whether I could write a paper about my results. As the topic did not t into any running project or at least the overall research directions of his group, he could have answered no. But instead, he encouraged me to do it. The paper became a success, and many other papers about new concepts and solutions followed. Now the answer is obvious: There exist better solutions. I have dealt with the topic over the past years. Now I want to share the basics as well as current research results with the reader. This book is surely not a bedside reading. But with all the presented concepts, it can broaden the mind of the reader concerning security, privacy, and RFIDsystems. Iwishthe reader many new insights. There are many people I would like to thank. First of all, my thanks go to my ] supervisor, Prof. Dr. Paul Muller. He gave me room for creativity and plenty of rope to work on my own.