Environment plays a major role in the evolution of galaxies. This is particularly true of low mass dwarf galaxies where more massive galaxies dramatically affect the local gravitational potential. Isolated galaxies offer a unique test bed for comparisons to theoretical models where the complicating physics of galaxy–galaxy interactions are minimized. For galaxies less massive than M_star < 10^9 M_sun, we have shown that ending star-formation requires the presence of a more massive neighbor. I will discuss follow-up HI observations in these systems and discuss the implications of these results for quenching mechanisms at all scales.