Technical documentation for social science data is produced by a range of technologies in a variety of environments. While statistical agencies generally standardise the content and the look and feel of the documentation they produce, each agency approaches the task differently. Documentation produced by individual researchers shows even more variety. This heterogeneity in documentation comes at a cost – for data archivists who have had to adjust to new documentation styles with each data deposit in order to curate the collection, and for secondary data analysts attempting to understand datasets with which they were not familiar.

Communities of potential or actual DDI users, particularly

The authors believe that it is currently premature to recommend a 'best practice' for interacting effectively with registries.Instead, this document defines registries and provides a justification for using them.It begins by giving relevant definitions and discussing the general business case and then goes on to describe from a high-level perspective the use of registries that allow researchers to access material.It concludes by describing examples of researcher use cases.

The benefits of using controlled vocabularies within DDI metadata creation are the primary underlying principles behind this Best Practice document.Use of a controlled vocabulary enhances consistency and efficiency in the production of DDI metadata, gives precision in searching the DDI metadata, and allows semantic and technical interoperability between organisations creating DDI instances.