More than five decades have passed since Charles Tiebout wrote his seminal 1956 paper, often cited as the classic apologetic for locally based systems of metropolitan governance. This essay traces the impact of Tiebout’s work and subsequent scholarship in public choice, identifying important lessons and lingering issues. Although public choice has demonstrated that polycentric systems are adept and flexible in producing and providing municipal services and a variety of interlocal agreements, the presence of municipal boundaries gives rise to a host of spillover problems, such as urban sprawl and segregation. These spillovers are particularly nefarious because, unlike the natural cooperation that seems to occur in service provision, municipalities tend to assert narrow self-interest in the face of these types of externalities. The essay proposes that, commensurate with the growing salience of equity among the pillars of public administration, interjurisdictional spillovers and their attendant equity impacts will be the central challenge for thinkers studying metropolitan governance in the 21st century.