This book has focused emphasis on concepts to reinforce wider application of knowledge so that one can apply it during exams as well as clinical life also. As a student of Pathology I have always felt that by understanding proper concepts we can apply our knowledge to solve unheard toughest puzzle also and that feeling I am trying to portray through this book. Nowadays, Examiners are asking mostly newer MCOs in their exams and to achieve topmost rank one cannot rely on solving MCOs of previous years only so student need to focus more on combination of learning concepts and applying them in solving all sorts of MCQs. Pathology is core subject for better understanding of intricacies of other subjects of medical stream so mastery of this subject will surely boost up your rank and knowledge both. I have tried my every effort to spread knowledge through this book which will be helpful for both MCO exams and acquiring clinical skills also.