Registers of disease serve a multitude of purposes, but are of particular importance to those interested in audit, in monitoring the introduction of new treatment or training programmes, in health service research, and in the planning of hospital services. The Nottingham Heart Attack Register has been in operation since 1973 and is proving to be an important data source. We present a brief history of the Register, describe how to set up a disease register and demonstrate how it can be of value to a wide range of health service staff using examples from our experience.