# desideratum

> bibliographic resource which a library wants to acquire

**Wikidata**: [Q12764554](https://www.wikidata.org/wiki/Q12764554)  
**Source**: https://4ort.xyz/entity/desideratum

## Summary
A desideratum is a bibliographic item that a library has identified as wanted for its collection but has not yet acquired. In library and information science, the term labels a gap that selectors actively try to fill through purchase, donation, or interlibrary transfer.

## Key Facts
- Classified as both a library-science concept (70 sitelinks) and an information-science concept (56 sitelinks)
- Plural form: desiderata
- Czech and Slovak Wikipedias maintain separate articles on the topic
- Wikidata entity Q12058283; Google Knowledge Graph ID /g/122mkyc2
- Czech National Library authority file ID “ph536666” lists preferred Czech heading “dezideráta”
- Turkish National Library term ID 000001182 cross-references the concept
- Only two inter-wiki sitelinks exist, indicating a niche but established technical term

## FAQs
### Q: Does “desideratum” refer only to books?
A: No. It can be any bibliographic resource—books, journals, maps, digital files, etc.—that the library wants to add to its holdings.

### Q: How is a desideratum different from an acquisition request?
A: A desideratum is the conceptual gap in the collection; an acquisition request is the formal step taken to close that gap. The first is the target, the second is the process.

### Q: Is the term used outside of Central European libraries?
A: The concept exists globally, but the label “desideratum/desiderata” survives mainly in Czech, Slovak, and some German-speaking library circles; English-speaking librarians more often say “wanted item” or “collection gap.”

## Why It Matters
Knowing what a library still lacks is as important as cataloguing what it already owns. Desiderata lists guide budgets, interlibrary loans, and donor campaigns; they turn vague collection hopes into trackable, shareable objects. By naming an unmet need, the term gives selectors, donors, and partner libraries a common language for prioritizing purchases and avoiding duplication. In digital projects, desiderata also flag missing volumes that could make or break the completeness of a corpus, influencing scanning policies and rights negotiations. Though a specialist word, it encapsulates the forward-looking side of librarianship: not just preserving, but deliberately building knowledge resources.

## Notable For
- One of the few library-science terms whose plural (desiderata) is more frequently used than the singular
- Survives in modern Czech and Slovak professional vocabulary while fading from English
- Bridges both library science (collection development) and information science (resource discovery)
- Serves as the conceptual opposite of “holdings,” defining completeness by what is absent

## Body
### Terminology & Scope
“Desideratum” entered library jargon from Latin, meaning “something desired.” It denotes any document—monograph, serial, audio recording, electronic resource—that selectors have identified as needed but have not yet obtained. Once acquired, the item ceases to be a desideratum and becomes part of the holdings.

### Usage Patterns
Contemporary Anglo-American libraries rarely use the word in public-facing catalogs; internal gap lists or “wants files” perform the same function. The term remains current in the Czech Republic and Slovakia, where national bibliographies and union catalogs maintain official desiderata files that libraries can query before acquisition or donation.

### Cross-Disciplinary Role
Because the concept links user demand, collection policy, and resource discovery, it straddles library science (practical selection, weeding, and acquisition) and information science (metadata design, retrieval algorithms, and system alerts that surface missing items).

## References

1. Wikibase TDKIV