The 11th Esteve Foundation Symposium was held from 6-9 October 2004 in S’Agaro (Catalonia, Spain) on the topic Drug Transport(ers) and the Diseased Brain with 20 speakers from 11 countries all over the world. Lectures and discussions centered on strategies to overcome brain barriers to deliver (biopharmaceutical) drugs to the brain to treat CNS-disorders like Alzheimer Disease, Parkinson Disease, multiple sclerosis, lysosomal storage diseases, or brain tumors.