A major driver in Aegilops tauschii introgressions comes from the observation that the diploid D genome progenitor possesses a higher genetic diversity compared to their corresponding genomes in bread wheat cultivars and landraces. Since the mid-twentieth century directed efforts at Ae tauschii introgressions into wheat has come from two avenues. Firstly, the more common approach of artificial hexaploid wheat synthesis that is generated by crossing tetraploid wheats with Ae tauschii and secondly, the process of direct introgression which involves Ae tauschii crosses with bread wheat and through repeated backcrosses to recover a stable bread wheat derivative. Additional refinements have also come from single Ae tauschii chromosome substitutions in wheat to generate sequential segmental introgressed blocks. Using these approaches, numerous traits with improvements to biotic and abiotic stresses, grain quality attributes and yield-related components have been successfully incorporated into common wheat and in some instances the causative genes identified.