The first part of the book introduces the array of tools currently in use in structure determination, originating from mathematical, computational and experimental approaches. It displays the variety and ingenuity of old and new phasing approaches developed to solve increasingly complex structures. Some of the papers focus on recent developments that have given older methods a new lease of life. Equally impressive are the presentations of newer approaches which take advantage of recent experimental, mathematical and computational advances. The second part of the book focuses on applications to macromolecular structures, displaying the incredible progress that has been achieved in recent years. The book concludes with a series of presentations on the latest developments, providing a view of the newest phasing methodologies. It offers the promise of many more achievements yet to come.