"From 1999 until April 2005, the DSP thesaurus was adopted as the Government of Canada Core Subject Thesaurus (CST) and during that period the two vocabularies were identical. In 2005, Library and Archives Canada assumed responsibility for the CST and the DSP thesaurus has been maintained and developed independently since then. The PDS thesaurus is a bilingual vocabulary consisting of two separate data files, English and French. The English and French versions of the thesaurus were developed and are maintained simultaneously and neither language is to be considered the dominant or source language in this vocabulary. Neither language is a translation of the other; they are each in a relationship of equivalence. The English thesaurus and the French thesaurus are identical in their coverage but their respective relational structures are not identical due to the natural conceptual and terminological differences between the two languages. The English vocabulary contains 2157 postable terms and 1698 non-postable terms. All postable terms are assigned to one or more of nineteen subject catagories.
Used as a source of subject descriptors for DSP catalogue records. As of 2009, the PDS Subject Thesaurus is also being used by Publishing and Depository Services as a source of descriptors for web metadata on the Publications Canada web site."