The second edition of this book has drawn heavily on the first edition but a huge amount of research on steroid analysis has been published over the last 15 years. As a result, the Editors decided to let the first edition of this book stand on its own and direct readers interested in pre-1995 steroid analysis to it, simply because the post-1995 research can on its own fill the second edition. We have tried to keep a balance but equally have allowed authors of each chapter a significant degree of freedom to approach their particular topics as they thought fit - they are after all the experts...