Local antibiotic treatment in bacteriological infections of outer or inner surfaces is more effective and less expensive than the systemic antibiotic therapy. In the ear local application of an antibiotic may be indicated in bacterial external otitis, in the suppurating radical cavity and perioperatively in chronic otitis media. - After a short survey on suitable antibiotics a study is presented, using the 0.2% solution of Ciprofloxacine for local application in bacterial external otitis (n = 34), infected radical cavities (n = 31) and external otitis complicating a chronic middle ear disease (n = 5). Dry ears, as a whole, resulted in 86%. These results were distinctly better than those obtained with systemic Ciprofloxacine treatment (63%). In pseudomastoiditis or complicating lymphadenitis a combined local and systemic Ciprofloxacine therapy was successful (n = 7). No adverse reactions were seen. - Local antibiotic treatment in the ear should be performed by the otologist, but not by the general practitioner or even the patient himself.