Health surveys in the workplace are an important part of epidemiology, needs assessment and health promotion. Since the workplace is changing rapidly with the use of computer networks, we examined the feasibility, validity and cost of health surveys using email and the World Wide Web (WWW). Five hundred systematically sampled university staff in a convenience sample of 10 English universities were surveyed using either email alone, email plus a WWW form or postal questionnaire. Response rates, speed of response, validity and costs were examined. The postal survey obtained the best response rate: 72% as compared with 34% for email alone and 19% for the WWW, but it was also the most expensive at 92p per reply, with 35p for email, and 41p for the WWW. Most of the electronic responses were made within five days. In 1997, the increased response rate justified the higher cost of postal questicnnaires. Email and WWW surveys are easy, quick and inexpensive to administer, and despite low response rates may be useful for pilot studies. The rapid changes in the spread and use of information technology means we have to keep reassessing the methods we use for health surveys in the workplace