Actinic keratoses (AKs) are intraepidermal tumours, which result from the proliferation of transformed neoplastic keratinocytes. They are typically induced by chronic exposure to ultraviolet radiation, and can often develop into squamous cell carcinoma (SCC). Six patients, who presented with AKs located on the head, face and chest, were treated with the immune response modifier, imiquimod, as a 5% cream five times per week for up to 8 weeks. The majority of patients experienced mild to moderate side-effects, consisting of erythema, itching and burning. Topical application of imiquimod for 4-8 weeks resulted in complete clearance in all patients. No new or recurrent lesions were observed during a 6-8 month follow-up period.