- Decide on your filter value-selection paradigm—either drill-down or parallel selection.
- Provide an obvious and consistent way to undo filter selection.
- Always make all filters easily available.
- At every step in the search workflow, display only filter values that correspond to the available items, or inventory.
- Provide filter values that encompass all items, or the complete inventory.
G. Nudelman: Best Practices for Designing Faceted Search Filters