When we began to prepare for the USMLE Step 1 early in our second year at Yale Medical School, we discovered that a myriad of sources was available for pathology review but none that were both comprehensive and organized in a fashion conducive to repetitive review. We found that the material in many of the resources was presented in outline form, which failed to organize the etiology, pathology, clinical findings, and treatment options of each disease in a consistent manner. Although we used the most highly rated pathology reviews, we still found ourselves combining information from multiple sources to create a more comprehensive and convenient review tool.Lange Pathology Flashcards are the result of our trials and tribulations while trying to learn pathology and review the subject for the boards. These cards offer the most complete, concise, and relevant high-yield information for the major diseases tested on the USMLE Step 1 and in the second-year pathology course. The content covers the most current and board-relevant information that can otherwise only be found by combining the content of several review sources. In this revised edition, we have added more, up-to-date high-yield disease processes and key information that is being tested on the Step 1.We are excited to present this high-yield pathology content in a format designed for active review. Each card provides a structured presentation of a specific disease and allows students to easily compare and contrast diseases. The introductory cards for each system describe the basic physiologic and/or pathophysiologic principles of the relevant structures and organs. Each disease-specific card contains both a clinical vignette and the characteristics of the disorder. The vignette appears on the front side of the card and frames the pertinent information in the context of a clinical application. The reverse side of the card includes information related to the etiology and epidemiology of the disease; classic or defining pathologic, pathophysiologic, or histologic findings; clinical manifestations, classic presentations, and current medical treatments; and pearls. In addition, the most salient features of each disease are highlighted in bold throughout each card for rapid review purposes.We would suggest using these cards as an adjunct to your pathology course materials early in your second year. Familiarizing yourself with these cards as you tackle your course will be immensely helpful to you during your Step 1 review. We would like to encourage you to jot down your own notes in the margins and make these cards your personal pathology review. We also encourage you to make your own cards for low-yield conditions that you identify.We hope that this updated edition of the Lange Pathology Flashcards will help prepare you for the boards and serve as a resource that will bridge your basic pathology knowledge with the clinical aspects of disease that you will soon be encountering firsthand on the wards.Best of luck with Step 1, and feel free to contact us with any suggestions to improve this study tool in the next edition.