B2 intermetallics have attracted significant interest for advanced structural materials, because of high melting point and high strength. Nonetheless, the limited plasticity of B2 intermetallics at room temperature severely hindered their practical applications. Here we utilized B2 CoAl intermetallic as a prototype to investigate several strategies of improving plasticity in brittle B2 intermetallics at room temperature. Three types of CoAl 100 nm/X 10 nm nanolaminate systems are constructed. In the first case, we examined CoAl/Fe nanolaminate with coherent interface. In the second case, we evaluated CoAl/Ni nanolaminate with incoherent interface and pre-existing dislocations in CoAl. In the third case, we investigated CoAl/Al-Co with amorphous intergranular film network and pre-existing dislocations in CoAl. In situ micropillar compression tests show significant synergy of high strength and room temperature plasticity in these nanolaminate systems. Transmission electron microscopy (TEM) studies coupled with molecular dynamics (MD) simulations reveal the effects of different types of interfaces and pre-existing dislocations on deformation mechanisms and work hardening capability in B2 CoAl intermetallics. The findings presented in this thesis provide a new perspective on improving room temperature plasticity in a wide range of brittle materials.