The second edition of this successful text expands on the depth and scope of the topic by bringing together many of the world's experts to provide a view of the current state of the field suitable for advanced undergraduate students, graduate students and beyond. The book begins with a description of the principles of protein, DNA and RNA structure, the methods used to collect the data, and how the data are represented, visualized and stored. With these prerequisites the comparative analysis of structure reveals classification schemes and how they are used in studies ranging from evolution to structure prediction. The physical properties of structure are explored to understand, for example, how macromolecules move and interact with each other and with ligands, offering insights into how drug discovery is undertaken and how structure can provide the details needed to understand complex molecular interactions important in fields such as immunology and systems biology. Finally, structural genomics reveals insight into the future role of structural bioinformatics where features, including function, are systematically assigned and the structural basis of complete organisms begin to emerge.