ViralORFeome is a database for creating and managing viral ORF clones. It includes a web interface to search and display viral sequences and annotations downloaded from GenBank. When users have identified the viral ORF sequences that they want to clone, clicking on target sequences automatically creates virtual clones in ViralORFeome database together with suitable cloning primers. These primers are designed for PCR amplification and cloning of viral ORFs using the Gateway Õ system. To determine if 'entry' clones produced at the bench exhibit expected sequences, sequence traces can be uploaded in ViralORFeome, automatically aligned, and compared to corresponding virtual clones. Finally, ViralORFeome database allows users to manage their collection of viral ORF clones, keep track of expression plasmids derived from 'entry' clones and share plasmids with other laboratories. System architecture and data flow are depicted in Figure 1 .