Glutamate is the most important excitatory neurotransmitter in the central nervous system. In the process, glutamate fulfills numerous physiological functions, but also plays an important role in the pathophysiology of different neurological and psychiatric diseases, especially when an imbalance in glutamatergic neurotransmission occurs. Under certain conditions, glutamate has a toxic action resulting front an activation of specific glutamate receptors, which leads to acute or chronic death of nerve cells. Such mechanisins are currently under discussion in acute neuronal death within the context of hypoxia. ischaernia and trauinas, as well as in chronic neurodegenerative or ncuronictabolic diseases, idiopathic parkinsonian syndrome, Alzheimer's dementia and Huntington's disease. It is hoped that glutamate antagonists will lead to novel therapies for these diseases, whereby the further development of glutamate antagonists for blocking disease-specific subtypes of glutamate receptors may be of major importance in the future. Copyright (C) 2003 John Wiley Sons, Ltd.