OBJECTIVES: To investigate patient preferences for attributes or characteristics associated with conventional and homeopathic treatment for asthma and to investigate the extent to which such preferences may differ between patient sub-groups. METHODS: The economic technique of conjoint analysis (CA) was used to investigate patients’ strength of preference for several key attributes associated with services for the treatment of asthma. A CA questionnaire was administered to two samples of asthma outpatients of 18 years or older, 150 individuals receiving conventional treatment at Whipps Cross Hospital, London, U.K. (WC) and 150 individuals receiving homeopathic treatment at the Royal London Homeopathic Hospital, London, U.K. (RL). RESULTS: An overall response rate of 47% was achieved (n=142) of which 72 were from the conventional treatment sample and 70 were from the homeopathic treatment sample. Statistically significant attributes in influencing preferences for both the WC and RL respondents were the extent to which the doctor gives sufficient time to listen to what you have to say, the extent to which the treatment seems to relieve your symptoms and the travel costs of attending an asthma consultation. In addition, the extent to which the doctor treats you as a whole person was also a statistically significant attribute for the RL respondents. CONCLUSIONS: This study has demonstrated that aspects associated with process of delivery of asthma services are important to patients in addition to treatment outcomes. The homeopathic respondents expressed stronger preferences for the doctor to treat them as a whole person in comparison to the patients receiving conventional treatment. Conjoint analysis is a potentially useful tool for assessing patient preferences for alternative modes of delivery of asthma services.