As of June 2005, there are 175976 sequences from environmental stress libraries made available in the public domain through EST projects in a variety of plants. Cross-referencing the available sequence data has several important applications including the identification of homologous sequences with putative roles in different kinds of stress. The identification of orthologous sequences is particularly important because of the similar roles and functions these sequence products will have across plant species. The PlantStressDB is a relational database containing ESTs from 118 cDNA libraries generated in response to single stress treatments such as heat, cold, and dehydration and salt stress. There are presently 16 species represented in the database including 6 monocots and 10 dicots. Tentative orthologous groups (TOGs) were identified using transitive, reflexive best hits across at least 3 species with a maximum of Blastn e-value of 1e-5. The relational database is being maintained on the SQL2000 server.