  We report on the distribution of metallicities, [Fe/H], for very metal-poor
stars in the halo of the Galaxy. Although the primary information on the nature
of the Metallicity Distribution Function (MDF) is obtained from the two major
recent surveys for metal-poor stars, the HK survey of Beers and collaborators,
and the Hamburg/ESO Survey of Christlieb and collaborators, we also discuss the
MDF derived from the publicly available database of stellar spectra and
photometry contained in the third data release of the Sloan Digital Sky Survey
(SDSS DR-3). Even though the SDSS was not originally planned as a stellar
survey, significant numbers of stars have been observed to date -- DR-3
contains spectroscopy for over 70,000 stars, at least half of which are
suitable for abundance determinations. There are as many very metal-poor
([Fe/H] < -2.0) stars in DR-3 as have been obtained from all previous survey
efforts combined. We also discuss prospects for significant expansion of the
list of metal-poor stars to be obtained from the recently funded extension of
the SDSS, which includes the project SEGUE: Sloan Extension for Galactic
Understanding and Exploration.
