The fourth edition of this book has been thoroughly updated and revised in accordance with the competency-based curriculum of Pathology. It has been structured in question-answer format that incorporates information in a concise manner with bulleted points for rapid review and easy recapitulation. This is an endeavour to make understanding of Pathology easier so as to facilitate learning by students and help them apply their knowledge to the problems they encounter in their clinical practice later in life. This edition is based on Robbins & Cotran, Pathologic Basis of Disease, 10th edition.