Topical corticosteroids are widely prescribed by dermatologists caring for patients with atopic eczema. Patients' fears about using topical corticosteroids may have important implications for compliance with treatment. We carried out a questionnaire-based study of 200 dermatology outpatients with atopic eczema (age range 4 months-67.8 years) to assess the prevalence and source of topical corticosteroid phobia. We also questioned patients on their knowledge of the potencies of different topical corticosteroids. Overall, 72.5% of people worried about using topical corticosteroids on their own or their child's skin. Twenty-four per cent of people admitted to having been non-compliant with topical corticosteroid treatment because of these worries. The most frequent cause for concern was the perceived risk of skin thinning (34.5%). In addition, 9.5% of patients worried about systemic absorption leading to effects on growth and development. The most commonly used topical corticosteroid was hydrocortisone, yet 31% of patients who used this preparation classified it as either strong, very strong or did not know the potency. Only 62.5% of the 48 patients who had used both Dermovate (Glaxo) and hydrocortisone in the past were able to correctly grade Dermovate as being more potent than hydrocortisone. The most common source of patient information regarding topical corticosteroid safety was the general practitioner. Although skin thinning and systemic effects can develop very occasionally in people using topical corticosteroids, the concern expressed by people using them seems out of proportion in relation to the evidence of harm. This study highlights the need for provision of better information and education to patients and possibly general practitioners regarding the safety, potency and appropriate use of topical corticosteroids.