Eagerly awaited, this second edition of a best–selling text comprehensively describes from a modern perspective the basics of x–ray physics as well as the completely new opportunities offered by synchrotron radiation. Written by internationally acclaimed authors, the style of the book is to develop the basic physical principles without obscuring them with excessive mathematics. The second edition differs substantially from the first edition, with over 30% new material, including:  A new chapter on non–crystalline diffraction – designed to appeal to the large community who study the structure of liquids, glasses, and most importantly polymers and bio–molecules A new chapter on x–ray imaging – developed in close cooperation with many of the leading experts in the field Two new chapters covering non–crystalline diffraction and imaging Many important changes to various sections in the book have been made with a view to improving the exposition Four–colour representation throughout the text to clarify key concepts Extensive problems after each chapter  There is also supplementary book material for this title available online ( http://booksupport.wiley.com ). Praise for the previous edition: “The publication of Jens Als–Nielsen and Des McMorrow’s Elements of Modern X–ray Physics is a defining moment in the field of synchrotron radiation… a welcome addition to the bookshelves of synchrotron–radiation professionals and students alike.... The text is now my personal choice for teaching x–ray physics…” – Physics Today, 2002