I would first like to acknowledge all the expert chapter authors associated with this textbook. Many of them have been close professional friends for many years, and I am deeply honored to be a colleague of theirs. I also worked closely with Mr. Robert Pancotti at McGraw-Hill in the production of the first edition of the book, and Ms. Cindy Yoo in production of the second edition. They are both effective editors. I would also like to extend my deepest thanks to the others at McGraw-Hill who have been involved in the production of this book. I am delighted that this book has been included in the Lange series of medical books, which has such a proud tradition in medical education.