The health professional's office environment has been identified as one of the potential influences on smoking behaviour of patients. This study compared characteristics of office smoking policies and environments of 30 physicians and 30 dentists using both telephone survey and site visit. The site visit was considered the 'gold standard'. The sequence of interview presentation was randomly reversed for half the physicians and half the dentists to control for order effects. Kappa estimates and two-way Analysis of Variance were used on categorical and continuous variables, respectively. The results show there was a high agreement between the two modes of surveying. Physicians and dentists do not differ in level of agreement and in the consistency of responses obtained by telephone and site visit. We conclude that a telephone survey is a valid method to obtain smoking-related information from health professional offices.