Are Institutional and post-Keynesian economists converging on a shared approach to understanding Modern Monetary Theory (MMT)? The literature suggests growing recognition that post-Keynesians and Institutionalists share a common intellectual history, conceptual frameworks, and overlapping professional memberships. For this reason, PostKeynesian Institutionalism (PKI) has emerged as a unifying approach to heterodox economics. In this review of the Modern Monetary Theory (MMT) literature, I explore the degree to which this PKI convergence extends, or fails to extend, to the historical, theoretical, and policy issues surrounding MMT. The point of this paper is to delineate where scholars from these traditions agree, where they specifically disagree, and to explore whether or how these disagreements may be ameliorated with respect to MMT.