At its core, OpenDMA (Open Document Management Architecture) defines an abstract model for Document Management and Enterprise Content Management Systems.

The OpenDMA API provides an abstract interface to this model. It allows to write content centric applications once, and run them against multiple different Enterprise Content and Document Management Systems.

An "OpenDMA Adaptor" implements this API for a specific ECM system, just like a database "Driver" in JDBC. There are adaptors available for multiple popular ECM systems like Alfresco, CMOD, Documentum, FileNet P8, IBMCM, Nuxeo, OnBase, OpenText Content Services, Sharepoint, and others.

The API is available for different programming languages and enforces a consistent style across these languages. A REST-ful API allows to bridge between programming languages and across the network. A Python application on one machine can talk to a Documentum OpenDMA Adaptor on a different machine which uses the DFC.jar Java API.