The metallicity distribution function of the Milky Way halo, as
determined from the Hamburg/ESO Survey.

The metallicity distribution functions (MDFs) of the components of the
Galaxy provide information on their chemical enrichment history, and
the MDFs are key observables of models Galactic chemical evolution
(GCE). I will report on determinations of the MDF of the Galactic
halo by means of statistically complete samples of metal-poor stars
selected with quantitative criteria from the Hamburg/ESO
objective-prism survey (HES). I will present comparisons with the
MDFs of dwarf galaxies as well as with predictions of GCE models.