The paper reviews different approaches to implementation of the central bank digital currencies (CBDC). Retail as well as wholesale CBDC are reviewed. Implications for the domestic and cross-border usage are analyzed. Based on the theoretical assumptions and practical cases available so far, different implementation models are classified and graded. The analysis shows that different CBDC implementation models for might require different level of central bank involvement and various impact on monetary policy. It also indicates that although significant adaptation of governance and technical procedures might be required, retail and wholesale CBDC may increase efficiency of the current payment systems, ensure higher transparency and availability of payments. However, for jurisdictions with limited payment infrastructure the costs of implementing CBDC might be prohibitive.