This webinar provides a structured overview of DDI-Codebook Version 2.6, presented at the start of the formal voting period for adoption into the DDI standard. The session was designed to support DDI Alliance voting members and reviewers by clarifying the scope, intent, and technical changes introduced in this incremental release. This release strengthens the precision, machine-actionability, and cross-system interoperability of DDI-Codebook metadata while maintaining backward compatibility and stability for implementers. Key enhancements include: More consistent attributes for people and organizations Better linking of access rules to specific content Expanded use of typeOfXxxx to support controlled vocabularies, making metadata more structured and interoperable More consistent use of controlled vocabularies through the element concept Updated internal enumerations A new DDI controlled vocabulary Metadata access information Use of SDTL, allowing clearer descriptions of file and variable derivations