Abundance evolution of high-z clusters

X-ray spectroscopy of the hot Intergalactic Medium (IGM) within Clusters of Galaxies has revealed that a significant enrichment has occurred during th eir evolution. The astrophysical mechanisms which have driven this enrichme nt have not however been quantitatively clarified yet. In this contribution we shortly review the present-day knowledge of clusters' chemical abundanc es and we discuss how future X-ray missions, notably SPECTRUM-RONTGEN-GAMMA , ASCA and XMM, could contribute to extend our knowledge to redshifts large r than z approximate to 0.4.