- selecting a keyword from the thesaurus,
- setting a standalone keyword.
1. Selecting a keyword from the thesaurus
Keywords can be selected from an existing, authorised list, called thesaurus. If the keyword is set form a thesaurus, the thesaurus itself must be cited (title, date, date type). One such authorised thesaurus is the General Environmental Multi-lingual Thesaurus (GEMET) used for INSPIRE needs. It includes INSPIRE data themes that are selected as keywords.
Keywords may also be set using other thesauruses, but it is required to include at least one keyword from GEMET - INSPIRE theme.When entering metadata, the INSPIRE data theme must be selected that best reflects the primary or the most important data resource component. To avoid double or multiple data classification, it is recommended to select only one GEMET-INSPIRE Data Themes.
A keyword from the GEMET-INSPIRE data theme must:
- be positioned in the element "Keyword (INSPIRE Theme)"
- be set independently (not in a group of keywords), separated from other, non-"GEMET-INSPIRE data themes" keywords,
- have an identical set of characters, being case-sensitive,
- include accompanying citation of the GEMET thesaurus (title, date, date type).
Table of Croatian NSDI spatial data themes
Citing the selection of an INSPIRE data theme from the GEMET thesaurus
| Keyword | Title | Date | Date type |
| geographic names | GEMET - INSPIRE themes, v.1.0 | 2008-06-01 | published |
Citing the selection of keyword value from the GEMET thesaurus
| Keyword | Title | Date | Date type |
| drainage system | GEMET - Themes, v. 2.4 | 2010-01-13 | published |
2. Setting a standalone keyword value
Independent keywords are not linked with the thesaurus. Instead, the metadata editor sets them as free text, assessing which keywords best describe a data resource. Entered keywords should not end with a comma or any special character, since that could lead into an error in checking metadata notations. In determining independent keyword, no link to the thesaurus of keywords is set.