Creeping and colonial bentgrasses (Agrostis stolonifera L. and A. capillaris L.) are economically important turfgrass species used extensively on golf courses. Currently several research groups are developing genetic linkage maps for these species. To eventually take advantage of the synteny among grass genomes for identification of genes controlling important traits it will be essential to place genes on the bentgrass genetic linkage maps. Marker development is a prerequisite to build a genetic map and EST libraries are a tremendous resource for the identification of gene-based markers. We have developed cDNA libraries from both creeping and colonial bentgrasses and sequenced random clones that can be used to develop markers for mapping bentgrass genes. Ten thousand clones from each library were randomly picked and sequenced from the 3' end. Vector and high quality trimming resulted in a total of 14,565 sequences (9.7 Mb) with an average read length of 666 bp. Of the total, 7,856 sequences (4.5 Mb) were from creeping bentgrass while 6,709 sequences (5.2 Mb) were from colonial bentgrass. Putative functions of each EST transcript were assigned by using BLASTX to search the SWISS-PROT protein database. The results will be used to organize each EST into gene ontology groups. The individual cDNA reads were assembled into contigs using the CAP3 program which assembled both libraries into 2,093 contigs with an average of 4.75 sequences per contig and an average length of 917 bp each. Preliminary analyses revealed numerous potential single nucleotide polymorphisms (SNPs) and indels between similar creeping and colonial sequences indicating that these EST libraries are a potential resource for marker development. Further progress in data analysis and mining of these EST libraries will be described.