The ability to mitigate interference from information that was previously relevant, but is no longer relevant, is central to successful cognition. Several studies have implicated left ventrolateral prefrontal cortex (VLPFC) as a region tied to this ability, but it is unclear whether this result generalizes across different tasks. In addition, it has been suggested that left anterior prefrontal cortex (APFC) also plays a role in proactive interference-resolution although support for this claim has been limited. The present study used event-related functional magnetic resonance imaging (fMRI) to investigate the role of these regions in resolving proactive-interference across two different tasks performed on the same subjects. Results indicate that both left VLPFC and left APFC are involved in the resolution of proactive interference across tasks. However, different functional networks related to each region suggest dissociable roles for the two regions. Additionally, regions of the posterior cingulate gyrus demonstrated unique involvement in facilitation when short- and long-term memory converged. This pattern of results serves to further specify models of proactive interference-resolution.