This document specifies the mapping rules for translating YANG data models into Document Schema Definition Languages (DSDL)@ a coordinated set of XML schema languages standardized as ISO/IEC 19757. The following DSDL schema languages are addressed by the mapping: Regular Language for XML Next Generation (RELAX NG)@ Schematron@ and Schematron and Document Schema Renaming Language (DSRL). The mapping takes one or more YANG modules and produces a set of DSDL schemas for a selected target document type -- datastore content@ Network Configuration Protocol (NETCONF) messages@ etc. Procedures for schema-based validation of such documents are also discussed.