IIregios

IIregios is a theoretical construct in regional planning and geography describing a transboundary dual-region system in which two neighboring regions coordinate across borders to manage shared resources, infrastructure, and development policies. The 'II' denotes duality: two interlocking regional blocks that maintain some autonomy while pursuing common objectives. In practice, a IIregio may be formal or informal, established through bilateral agreements or treaties, and supported by a joint coordinating council, shared data platforms, and harmonized planning standards. Typical areas of collaboration include transportation corridors, water and energy management, environmental protection, housing and land use, and economic development.

Origins and reception: the term has appeared in regional studies and planning debates since the early 21st century, used to analyze cross-border urban regions and to propose governance models that go beyond municipalities. Variations of the concept emphasize different scales, from two large blocks to networks of subregions that collaborate under a common framework while retaining local governance. Criticism centers on sovereignty concerns, unequal bargaining power between sides, funding and implementation challenges, and difficulties achieving data interoperability and policy alignment.

See also: cross-border region, bi-national metropolitan area, transboundary governance.