(1) Symptomatic treatment of atopic dermatitis is initially based on simple measures and moisturising creams. Topical corticosteroids are reserved for treatment of inflammatory exacerbations. (2) After topical tacrolimus, marketing authorisation has been granted in France for a second topical immunosuppressant, pimecrolimus, as a short-term symptomatic treatment for atopic dermatitis in children from the age of two years, and intermittently for long-term prevention of new exacerbations. (3) Short-term treatment with pimecrolimus has been tested in three trials in children with mild to moderate dermatitis (against the excipient), in one adult trial against the excipient, and in one dose-finding study in adults that included a group treated with topical corticosteroids. (4) Longer term treatment periods of 6 to 12 months have been tested in two trials versus excipient in children, and two adult trials, one versus moderately active topical corticosteroids. (5) These trials show that pimecrolimus works better than the excipient, but not nearly as well as moderately active topical corticosteroids. Pimecrolimus has not been compared with topical corticosteroids in children, the age group most vulnerable to atopic dermatitis. (6) The commonest adverse effects observed in clinical trials were local and included a burning sensation at the site of application and skin infections. Systemic adverse effects (mainly infections) were most marked in infants. Long-term risks, especially the risk of skin cancer, have not been assessed. (7) In practice, the reference treatment for exacerbations of atopic dermatitis is a topical corticosteroid; in children, it seems best to begin with a weak preparation. There is no reason to use pimecrolimus, which is less active than topical corticosteroids and whose potential long-term adverse effects, especially in children, are unknown.