The prevention and treatment of periodontal disease is based on accurate diagnosis, reduction or elimination of causative agents, risk management and correction of the harmful effects of the disease. The practice of risk assessment involves dental care providers identifying patients and populations at increased risk of developing periodontal disease. This can have a significant impact on clinical decision making. Risk assessment reduces the need for complex periodontal therapy, improve patient outcome and, ultimately, reduce oral health care cost. The awareness of risk factors also helps with the identification and treatment of co-morbidities in the general population as many periodontal disease risk factors are common to other chronic diseases such as diabetes, cardiovascular diseases and stroke.