The presence of the blood-brain barrier poses a huge challenge to effective delivery of therapeutics to the centra! nervous system. Therefore, many diseases of the centra! nervous systems, such as Alzheimer's or Parkinson's disease, multiple sclerosis and brain tumors cannot be successfully treated. ln recent years, interest has been expressed in using the nasal route far delivering drugs to the brain, exploiting the olfactory pathway. Numerous studies in animal models have reported evidence of nose to brain delivery of many different drugs, including neuropeptides. T he factors affecting the rate and extent of drug transport to the brain are molecular weight, lipophilicity and ionization of the drug. Studies in man have mostly compared the pharmacological effects of nasally and parenterally applied drugs. The results have confirmed the likely existence of a direct nose to brain pathway in humans, but demonstration of the clinical feasibility of nose to brain drug delivery is still doubtful. There is an increasing need far a nasa! drug delivery system that would improve the efficiency of the direct nose to brain pathway. Novel approaches capable to combine active targeting of a formulation to the olfactory region with mucoadhesive characteristics and controlled drug release will probably enhance the therapeutic use of this pathway.