The second edition of the book has been carefully pruned to suit the needs of undergraduate medical students in an aim to make them understand the biochemical concepts rather than memorizing them. The illustrations have been made instructive and visually appealing. Chapter summary and the review questions at the end of each chapter provide an opportunity for the students to revise and evaluate their understanding of the topics discussed. Applied, important and interesting concepts have been put into boxes to make them attractive for the students. Supplementation of the reading material with the clinical case studies is an effort to make the subject relevant to medicine and to introduce the students to the clinics.