Indices are the most important tools to measure, quantify and treat periodontal disease in both clinical and epidemiological situations. They are mainly based on the prevailing understanding of parthenogenesis of the disease. However, there is a dearth of literature on collective information of all the periodontal indices formulated to the date. This book collectively describes the evolution and the present concept of formulation of periodontal indices based on the multifactorial nature of periodontal disease.