Book excerpt: The study of the extracellular matrix (ECM) and its diverse roles in tissue scaffolding and cellular signaling in both physiological and pathological processes has significantly expanded over the past decade. Although well appreciated, the structural and biochemical complexity and the dynamic nature of the living matrix are still under extensive inv- tigation, yielding a growing number of methods with varying degree of sophistication and intricacy. In this edition of Extracellular Matrix Protocols, we compiled a variety of methods that can be readily reproduced in most cell biology laboratories, as well as several cutting-edge technologies that are indeed available in a limited number of centers, but are well worth the awareness and exposure to the ECM research community. As in the previous edition, the book chapters are divided into sections that rep- sent molecular biology techniques to study gene expression, biophysical and biochemical methods for the analysis of structure and composition, cell biology methods for the asse- ment of cell behavior and matrix assembly and tissue engineering applications. All chapters were contributed by scientists who developed the methods or mastered and perfected methods that were routinely used in their laboratories. An effort was made to provide practical working details and helpful notes for the nonexpert user in order to assist reproducibility and accuracy. We hope that these valuable protocols will become helpful tools for ECM researchers and will be further developed and tailored to the s- cific needs of a growing number of applications.