The NINOS Division of Clinical Research (DCR) is charged with ensuring the highest quality of each NINOS-funded clinical research project in terms of both conduct and the integrity of resultant data and\ ensuring compliance with DHHS/NIH/NINDS regulations regarding human subject protection and safety monitoring. To ensure the highest quality product and most efficient use of resources, DCR has established a programmatic requirement for clinical research-related scientific and technical support for NINDS-sponsored clinical research in the form of an NINDS Center for Clinical Research Resources. The Contractor shall provide scientific and technical support toward the conduct of NINOS-sponsored clinical research in the areas of Quality Control/Quality Assurance clinical trial monitoring, statistical and methodological support, clinical data acquisition and archiving support and common data element development support. The level of effort requirements of the base contract represent severable services that are continuing and recurring in nature. Despite the extensive performance history of this contract, the NINDS still have no way of knowing, even within a reasonable range of estimation, the exact course of action that will need to be taken in order to perform the four Performance Area support functions contained in the Statement of Work (Monitor Quality Assurance/Quality Control in Clinical Research; Statistical and Methodological Support; Clinical Data Acquisition and Archiving; and Common Data Element support) in any given year. Therefore, the most that the NINDS can fairly bargain for is that the Contractor have available and provide a cadre of personnel to be able to devote to the specific performance requirements as they are identified. Thereby, the Contractor's performance obligation and the Government's need can only be defined in terms of the expected level of effort that can be provided on an annual basis, for each 12 month period, as a means of defining the Contractors performance obligation and the Government's need for the basic requirement. The clause at FAR 52.232-20, Limitation of Cost, is included and is made a part of this contract and applies to the base contract and each successive option period so exercised.