This book is entitled "Dental caries and its diagnosis." The Speciality of Conservative dentistry has changed over the years, with the changing concepts of dental caries process, from the use of visual and tactile methods for diagnosing dental caries to the use of the most advanced diagnostic techniques with high sensitivity and specificity for caries diagnosis. Knowledge does not spread by keeping a lantern on one's own head, but it is by spreading the knowledge of "Dental caries and its diagnosis" its etiology, caries process, clinical manifestations and newer advances in its diagnosis through the words by this book. Sincere attempt was made to include figures for better understanding of the subject. More emphasis is given on the newer advances in caries diagnosis.