The Specification Domain, like its predecessors TMG and TMWG, develops specifications that set out the rules for how to design UN/CEFACT standards (Technical Specifications) and how these standards should be developed (Methodologies). When appropriate, the specifications are published also as ISO standards, e.g. the UN/EDIFACT syntax (ISO 9735) and the Core Components Technical Specifications (ISO 15000-5).

Although the primary target audience is UN/CEFACT and its standards development groups, the specifications are widely used also by other organisations for production of non-UN/CEFACT deliverables.

The purpose of the Specification Domain is to provide all UN/CEFACT Groups with Meta (base) Business Process, Information and Communications Technology specifications, recommendations and guidance. 

Upon request by the Bureau, the Specification Domain shall also function as a research group evaluating new information and communication technologies (ICT), as well as techniques and methodologies that may assist UN/CEFACT and its groups to fulfil their mandate and vision in Trade Facilitation and e-Business.

 •	UN/EDIFACT Message Design Rules
•	UN/EDIFACT Syntax Specification
•	UN/CEFACT Modelling Methodology, UMM
•	UN/CEFACT Core Components Technical Specification, CCTS
•	Core Components Business Document Assembly Specification, CCBDA
•	XML Naming and Design Rules, XML NDR