The epidemiology of Hepatitis B infection is used to show that dental health care workers are at greater risk of acquiring serious infective diseases than is the population at large. The significance of this greater risk is that dental employers must take the proper steps to protect their employees' health. A five fold strategy is put forward to achieve this end. The law governing a (dental) employer's duty in this regard is examined. Failure to take appropriate action leaves the dental employer open to legal action in the event that an employee acquires a serious infection in the course of his work. The similarity is stressed between Irish and British law in protecting the needs of authority and established bodies such as for instance the dental profession. However, the developments in Irish law are mentioned which show that following established practice in a profession does not guarantee protection from legal suit.