We present here a new approach to understanding the metallicity distribution function ob-
served for the globular clusters in the Milky Way.To explain the metal poor peak we adopt
the classical picture of primaeval formation of star clusters during the first big star
formation process of the Galaxy,but for the metal rich peak we propose a picture where the
origin of these star clusters is within the Galactic disc.Some specific physical process,
(probably kinematic-gravitation aggregation of individual stars by open clusters expelled from the thin disc by supernova explosions to form globular clusters in the thick disc,
as shown by the very similar metallicity distribution function observed in metal rich globular clusters and in the stars of the thick disc) with a long characteristic time
constant,yields a situation where the most recent peak in thin disc star formation, at
[Fe/H] = -0.2, has not yet given rise to a significant peak in the globular cluster
distribution,while the two earlier less metal rich peaks in the thin disc star formation rate have given rise to corresponding peaks in globular cluster formation. In this way
we can reproduce rather well not only the general trend observed in the metallicity
distribution function of the globular clusters, but also the two observed peaks in the
distribution observed at [Fe/H] = -0.4 and -0.7.