This paper discusses the piloting of a computerised decision aid that provides individualised information about hypertension to patients. The program is based on decision analysis, using decision trees as a way of structuring information. It incorporates the Framingham risk equation to assess a users' risk of coronary artery disease, together with a detailed assessment of the patient's current lifestyle and their willingness to change behaviour. Users of the program can decide how much or how little information they access. The program assesses individual's preferences for different treatment outcomes, before providing them with guidance on what might be the best treatment option for them. The program was evaluated by 10 patients with a diagnosis of mild to moderate hypertension and 8 health care professionals. Overall, both health care professionals and patients assessed the program positively. The use of a decision aid based on decision analysis may be a useful way of providing information to patients in order to promote shared decision making.