The Hustedt Centre combines a taxonomic collection (registered in Index Herbariorum with the acronym BRM) and a research facility targeting diatoms, one of the main primary producer groups in aquatic habitats. The publicly available database of the Hustedt Centre, containing information on accessions, specimens and references, is the first entry point for external users. Non-type microscopic slides and material are also available for loan and slides and material present in the collection are fully available for on-site investigation to visitors. Usage statistics below include on-line users and are rough estimates based on total number of unique visitors per year - around 1300 - multiplied by proportions of page views by geographic category.