GenBank(®) is a comprehensive database of publicly available DNA sequences for 300,000 named organisms, more than 110,000 within the embryophyta, obtained through submissions from individual laboratories and batch submissions from large-scale sequencing projects. Daily data exchange with the European Nucleotide Archive (ENA) in Europe and the DNA Data Bank of Japan ensures worldwide coverage. GenBank is accessible through the NCBI Entrez retrieval system that integrates data from the major DNA and protein sequence databases with taxonomy, genome, mapping, protein structure and domain information, as well as the biomedical journal literature in PubMed. BLAST provides sequence similarity searches of GenBank and other sequence databases. Complete bimonthly releases and daily updates of the GenBank database are available by FTP. GenBank usage scenarios ranging from local analyses of the data available via FTP to online analyses supported by the NCBI web-based tools are discussed. To access GenBank and its related retrieval and analysis services, go to the NCBI home page at www.ncbi.nlm.nih.gov .