In this paper the microstructure/property relationships of Ti-alloys (α+β and β alloys) and high strength, age-hardened Al-alloys are discussed. Common features in these microstructure/property relationships can be found for α+β Ti-alloys and Al-alloys in the underaged condition as well as for β Ti-alloys and Al-alloys in the overaged condition. Basic differences are the presence of dispersoids and large Fe and Si containing inclusions in Al-alloys and the alloying element partitioning effect in bi-modal structures of α+β Ti-alloys.