In facing the drafting a national level spatial plan, we find it necessary to rescale the Nomenclature of Territorial Unit for Statistics in Taiwan and/or establish a new spatial planning unit named metropolitan-region for implementing related multi-scalar spatial plans. The evolution of the discourses of planning metropolitans and regions in Europe and the United states is reviewed, and it is concluded that economic competitiveness, environmental protection, public service efficiency and social cohesion are now emerging as four equally important planning objectives. Nevertheless, thorough examination of the embedded socio-spatial praxis in Taiwan is needed to embark on the institutionalization of good metropolitan-regional governance.