The Mo 2-x W x BC system demonstrates the potential to optimize hardness, ductility, and sustainability in synthetically accessible inorganic materials for applications requiring wearresistant, superhard materials. In this work, bulk compressibility of Mo 2-x W x BC solid solu-tions, where x= 0, 0.5, and 0.75, were evaluated through in situ hydrostatic, high-pressure synchrotron diffraction experiments to ∼54 GPa, ∼55 GPa, and ∼60 GPa, respectively.