Nano-lamellar materials with ultrahigh strengths and unusual physical properties are of technological importance for structural applications. However, these materials generally suffer from low tensile ductility, which severely limits their practical utility. In this talk, we show that markedly enhanced tensile ductility can be achieved in coherent nano-lamellar high-entropy alloys, which exhibit an unprecedented combination of over 2 GPa yield strength and 16% uniform tensile ductility. The ultrahigh strength originates mainly from the lamellar boundary strengthening, whereas the large ductility correlates to a progressive work-hardening mechanism regulated by the unique nano-lamellar architecture. The coherent lamellar boundaries facilitate the dislocation transmission, which eliminates the stress concentrations at the boundaries. Meanwhile, deformation-induced hierarchical stacking-fault networks and associated high-density Lomer-Cottrell locks enhance the work hardening response, leading to unusually large tensile ductilities. The coherent nano-lamellar strategy can potentially be applied to other alloys and open new avenues for designing ultrastrong-yet-ductile materials for technological applications.