Ultramafic soils cover large areas in the Balkans.Our studies have shown that the number of the Alyssum hyperaccumulator taxa on the Balkan Peninsula is 17. The majority of the Ni hyperaccumulators are serpentine endemics.The highest Ni concentrations are recorded in A. murale, AL,BG,GR(-34690mg kg−1) and A. heldreichii GR (1440-32040mg kg−1) . A. murale with more than 2% Ni in leaves is the dominant species on all serpentine sites. The Ni concentrations recorded in A. murale leaves ranged from 0.5% to1.5% in BG, while it ranged from 0.07% to 1.3% in SR.  Ni concentration is highly dependent on the biology of the species, and edaphic factors. The concentration of Ni in A. markgraii from serpentine sites in Kosovo ranged from 1586 to 7564 mg kg−1. Among species of Thlaspis.l. the highest Ni concentrations are measured in Noccaea ochroleuca (15-23400 mgkg-1).The measured concentrations of Ni in the endemic Bornmuellera species restricted to Greece, Kosovo, Serbia, and S. Albania were in the range 1590-31200 mg kg-1. The endemic Greece Ni hyperaccumulator Leptoplax emarginata shows Ni concentrations between 2040 and 34400 mgkg-1. It is clear that several efficient populations of A. murale and L. emarginata displayed the best Ni-efficiency for phytomining.