The RAST (Rapid Annotation using Subsystem Technology) Server provides high quality genome annotations for prokaryotes across the whole phylogenetic tree. It makes a SEED-quality annotation available as a service with a 48 hour turnaround time. The SEED environment and SEED data structures (most prominently FIGfams) are used to compute the automatic annotations; however data is not added into the SEED automatically. Once annotation is completed, genomes can be downloaded in a variety of formats or viewed online. The genome annotation provided does include a mapping of genes to subsystems and a metabolic reconstruction.