More and more people are using the Internet as a source of information on health and mental health issues. Assuring quality and preventing abuse of the medium for the provision of health and mental health information is an increasing concern. This can be particularly important for more at-risk populations, such as people with chronic diseases and mental health concerns. This chapter presents the current situation of the health and medical Internet usage and the actions that have been taken to improve the quality of medical and health information. The chapter will particularly describe the methodology used by Health On the Net Foundation (HON), an international organization that has been certifying medical websites since the beginning of the Internet era. HON’s goal is to guide healthcare consumers and providers on the Internet to sound and reliable medical information. By certifying sites that adhere to its eight ethical guidelines (the HON Code), HON seeks to contribute to better, more accessible healthcare. HON certification is free and thereby available to all, and not subject to conflict of interest concerns that can arise from client-provider relationships. The HON code provides a transparent, flexible, accessible, and reliable methodology that promotes and improves the quality of medical websites worldwide. The success of the HON Code attests to its growing importance and the suitability of its methodology. More than 7,500 websites have been certified in 34 languages from 118 countries; 450 of these websites are related to mental health. In 2007, the French National Health Authority mandated that all health websites in France be certified by HON.