  Present and upcoming NASA missions will be intensively observing a selected,
partially overlapping set of stars for exoplanet studies. Key physical and
chemical information about these stars and their systems is needed for planning
observations and interpreting the results. A target star archive of such data
would benefit a wide cross-section of the exoplanet community by enhancing the
chances of mission success and improving the efficiency of mission
observatories. It would also provide a common, accessible resource for
scientific analysis based on standardized assumptions, while revealing gaps or
deficiencies in existing knowledge of stellar properties necessary for
exoplanetary system characterization.
