The purpose of this Program Announcement is to encourage the development and/or validation of new in vitro and in vivo models of HIV or HAART-related neurotoxicity that show promise for use in the screening of novel CNS and PNS-targeted therapeutic compounds. Ideally, such models would facilitate the screening of compounds or therapeutic approaches which protect neuronal and glial cells of the CNS from damage in response to HIV and possibly other stresses, such as injury or associated inflammatory insults.