Previous surveys of dental care have shown that a substantial proportion of people do not attend dentists regularly. Reasons given for such non-attendance included fear as well as other negative attitudes. Recent studies have attributed fear of dentistry to painful traumatic experiences. The purpose of this study was to compare regular and irregular or non-attenders for dental check-ups on a number of variables, including sex and age, self and family dental anxiety, and previous dental experience. A sample of 531 subjects of both sexes and ranging in age from 16 to 78 years was made available by two large organizations in London and surveyed during office hours. Dental anxiety appeared as a significant factor in non-attendance but there was little support for a simple conditioning hypothesis to explain dental anxiety. Attenders and non-attenders differed markedly in their perception of dentists but there was no difference between the groups as to sex and age.