Description: The Document Description consists of bibliographic information describing the DDI-compliant document itself as a whole. This Document Description can be considered the wrapper or header whose elements uniquely describe the full contents of the compliant DDI file. Since the Document Description section is used to identify the DDI-compliant file within an electronic resource discovery environment, this section should be as complete as possible. The author in the Document Description should be the individual(s) or organization(s) directly responsible for the intellectual content of the DDI version, as distinct from the person(s) or organization(s) responsible for the intellectual content of the earlier paper or electronic edition from which the DDI edition may have been derived. The producer in the Document Description should be the agency or person that prepared the marked-up document. Note that the Document Description section contains a Documentation Source subsection consisting of information about the source of the DDI-compliant file-- that is, the hardcopy or electronic codebook that served as the source for the marked-up codebook. These sections allow the creator of the DDI file to produce version, responsibility, and other descriptions relating to both the creation of that DDI file as a separate and reformatted version of source materials (either print or electronic) and the original source materials themselves.