The National Library of Medicine (NLM) of the National Institutes of Health (NIH) serves both as a traditional archive of medical literature and as a provider of computer-based access to electronically stored biomedical information. The National Center for Biotechnology Information (NCBI) and the Lister Hill Center for Biomedical Communication (LHNCBC) are research centers within the NLM concerned with the development of information systems for medicine and biotechnology. The most important elements of this contract are the provision of hardware and software maintenance for the computer systems. NCBI is a provider of database software and services to the biotechnology research community. Therefore it is imperative that the computing infrastructure on which those services depend the maintained in a state of optimum operational efficiency. Similarly, availability of research computing resources are vital to continued progress on LHNCBC's Congressionally mandated research projects. The work of both Centers requires that on-site hardware maintenance be readily available and that systems software be kept up-to- date. The second aspect of this contract is the enhancement of these computing resources through new systems acquisition and the upgrading of existing systems. The NLM, NCBI and LHNCBC are leaders in on-line information services and informatics research. Information systems technology improves so rapidly that purposeful planning for new systems acquisition and upgrades to existing systems are essential in order for the Library and the Center to maintain their leadership roles.