ISO 20022 describes a Metadata Repository containing descriptions of messages and business processes, and a maintenance process for the Repository Content.

The Repository contains a huge amount of financial services metadata that has been shared and standardized across the industry. The metadata is stored in UML models with a special ISO 20022 UML Profile. Underlying all of this is the ISO 20022 metamodel - a model of the models. The UML Profile is the metamodel transformed into UML. The metadata is transformed into the syntax of messages used in financial networks. The first syntax supported for messages was XML Schema.

The ISO 20022 message dashboard gives an overall picture of the five financial business domains in scope of ISO 20022. Its purpose is to show which business processes are already supported either by existing ISO 20022 message definitions or by candidate message definitions covered by an approved Business Justification. 5 domains:

The Standard is issued by ISO Technical Committee 68 (TC68), which is responsible for Financial Services in ISO. The Standard is managed by Working Group 4 (WG4), a sub-group of TC68 whose charter is "the management of ISO 20022". The Standard defines a Repository Management Group who manage the content of the Repository. SWIFT is the Registration Authority for ISO 20022.