More than ten years ago, when I first read Mario Gandelsonas' book The Urban Context, the beautiful abstract diagrams that the book presented -the street network of Chicago- fascinated me with the profound historical and cultural background that they suggested. Without knowing how this would direct me, I started to draw something related with the street network of Beijing. That is the beginning of this book. Among tons of the diagrams that I have created, most of them have not been incorporated into this book, while they have directed me into this fascinating research area which focuses on the "mineralized skeleton," rather than the "soft tissue" of urban forms.It was not until the recent five years when Yang and I came across some theories and approaches in paleontology that we started to integrate them into the street network study in Beijing and Savannah. Paleontology methods lay the foundation and provide a systematic and scientific platform for our research. Then urban paleontology, as a new framework for urban form study, unfolds itself more and more apparently in front of us. It explores the evolution of "urban species" based on their remains- "urban fossils," which describe distinct urban forms with imprints of their street networks. Just as how a biological fossil serves as a factual documentation of certain life forms, an urban fossil provides clues of the existence and transformation of urban forms.The study of urban paleontology inevitably directs us to further exploration in the fields of biology, anatomy, archeology, geology, and the application of computer aided design in the excavation of urban sites. Upon finishing this book, we realize that our work is too inadequate to possibly incorporate all the influence that other disciplines may have on architecture and urban design. What it has suggested is that architecture presents such a wide array of connections with other disciplines and becomes more and more towards an interdisciplinary study. We hope this book has illustrated the diversity of problems that invite further study and can serve as a start point for architects to conceive the total spectrum.-Ming Tang