Retail central bank digital currencies (rCBDCs): a comparative taxonomy of models and implementation strategies

This article frames retail Central Bank Digital Currencies (rCBDCs) as socio-legal implementation projects. It addresses a methodological gap in the literature by importing concepts from implementation science to analyse how rCBDCs move from policy intent to operational deployment and (critically) how they secure (or fail to secure) legitimacy and sustained adoption by end users. The article distinguishes process models (suited to pre-issuance projects) from determinant frameworks (suited to launched systems) and operationalises a three-level lens (institutional, organisational and systemic) to capture the interaction between legal mandates, intermediary architectures and citizen uptake. On this basis, it replaces the top-down/bottom-up binary with a comparative taxonomy of four implementation models: (i) technocratic-sovereign, exemplified by China’s e-CNY; (ii) regulated-concerted, emerging in the Eurosystem’s digital euro; (iii) market-platform, articulated in the United Kingdom’s digital pound; and (iv) developmental, illustrated by the Bahamian sand dollar and Nigeria’s eNaira. The comparative findings show that similar technical infrastructures can yield divergent legal and economic outcomes depending on a series of determinants, such as governance, privacy/AML, trust and infrastructure. The article concludes by outlining a minimum normative framework for rCBDC implementation, positioning implementation quality as the decisive variable in the legal sustainability of digital sovereign money.