There exists a gap in the use of Internet for health purposes between patients and health professionals and between various countries. The Internet has the potential to be a global tool for health professionals and their patients but, as seen in other fields, cultural differences may lead to divergent opinions and preferences. To identify the opinions, preferences and types of behaviours regarding the use of Internet for health purposes, for health professionals and patients in selected regions of the United States and Europe. An announcement of an online survey was posted on more than 100 web sites during May and June of 2002. Members of HONnewsletter were also invited via email. The online questionnaire consisted of 28 questions with sections designed specifically for patients or health professionals. Sub-samples of respondents were created based on their geographic location. 2621 respondents mainly from the United States (38%, n = 984) and Europe (29%, n = 739) completed the survey. For the USA, the majority of respondents were patients (68.7%), while in Europe, the majority were health care professionals (63.6%). In both regions, health professionals preferred using medical search tools but patients preferred general search tools. Concerns about the accuracy of information and trustworthiness were shared by all groups. The majority of respondents reported that they preferred certified web sites. The patients from USA (69%) and Europe (47%) have discussed the results of their Internet searches with their doctors, while health professionals are receptive to the discussion and find it helpful. Other e-health behaviours are also reported by both parties. Based on the self- reported e-health behaviours noted in this study it appears that the use of the Internet for health purposes is growing in importance to the patient-physician relationship in Europe and the USA.