Here, we introduce wild rice resources collected all over the world. They are composed of 9 genomes including 19 species of 1725 accessions. "Core Collections" are made for the convenience of research work. Core Collection Rank 1 contains 44 accessions, Rank 2 contains 65 accessions and Rank 3 contains 173 accessions selected as typical accessions from every species. They are also available to request for distribution and to make reference for phenotype data, though some of them are still in preparation. Core Collections are convenient to use all species for comparative analysis. All seeds or plants (especially for perennial strains) and phenotypic data of Core Collections will become available till the end of 2007. However, we are sorry for the inconvenience of setting a limit of five seeds for distribution, because of laborious work in propagation and small number of seed setting. Please follow the instruction of the cultivation manual when you try to grow wild rice. You can access the request form, phenotype data and MTA through each item you have chosen. After MTA being exchanged between the NIG (National Institute of Genetics, Japan) and your institute, we will send the seeds collect on delivery (C. O. D.) for mailing cost.