The discovery of a neuroprotective treatment is a high priority for research in Parkinson's disease. Substantial progress has been made towards this goal in recent years, but at the present there is still no treatment which can be said to have proven neuroprotective effects. There is no single unifying model to account for the disease; indeed it seems likely that the etiology is a convergence of several causes. This multiplicity may prove helpful, because mitigation of only one or a few of the factors may produce clinically important benefit. This review emphasizes the strategies for discovery of new treatments. Current approaches to the development of neuroprotective treatments can be broadly characterized into three groups: 1) approaches based on the existing understanding of the mechanism of cell injury and death in PD; 2) approaches based on clues from the emerging knowledge of genetics of PD; and 3) approaches based on clues from the epidemiology and role of environmental factors in the etiology of PD. Some specific compounds and approaches are discussed to illustrate these strategies. © 2004 Bentham Science Publishers Ltd.