  I present an overview of important results obtained using high-resolution
very long baseline interferometry (VLBI) observations of X-ray binary systems.
These results derive from both astrometric observations and resolved imaging of
sources, from black holes to neutron star and even white dwarf systems. I
outline a number of upcoming developments in instrumentation, both new
facilities and ongoing upgrades to existing VLBI instruments, and I conclude by
identifying a number of important areas of investigation where VLBI will be
crucial in advancing our understanding of X-ray binaries.
