The purpose of this contract is to provide immediate and comprehensive customer support, primarily by telephone, to users of NLM's MEDLARS databases. This includes answering user inquiries and troubleshooting problems in a real time mode. Support is provided to MEDLARS command language searchers and to those using NLM's Grateful Med search software for conducting MEDLARS searches. The primary means of providing Customer support is by telephone via a 'help desk' called the MEDLARS Service Desk. User inquiries also are handled by fax, mail, and electronic mail.