The clerkship curriculum that evolved into the ideas for this edition was inspired by two talented and forthright students, Philbert Yao and Chuck Rosipal, who have since graduated from medical school. It has been a tremendous joy to work with the excellent pediatricians at the University of Texas Medical School at Houston. I am greatly indebted to my editor, Catherine Johnson, whose exuberance, experience, and vision helped to shape this series. I appreciate McGraw-Hill's believing in the concept of teaching through clinical cases, and I would like to especially acknowledge Catherine Saggese for her production expertise, Cindy Yoo for her editorial guidance, and Anupriya Tyagi for her excellent production skills. At the University of Texas Medical School at Houston, we appreciate Giuseppe N. Colasurdo, MD and president of the University of Texas Health Sciences Center for his support and dedication to student education. Without the encouragement from my chairman Dr. Sean Blackwell, a wonderful clinician, administrator, scientist, and leader, and Dr. Patricia Butler, Vice Dean for Educational Programs, who inspires us all to be excellent educators, I could not have succeeded in this endeavor. Most of all, I appreciate my ever-loving wife Terri, and my four wonderful children Andy, Michael, Allison, and Christina, for their patience and understanding in the writing process.