SRU is a feature proposed by default by Koha if Zebra is used. With Elasticsearch you need to activate (or rather from a librarian point of view, ask your vendor to activate) it with this procedure (if I understand well) https://wiki.koha-community.org/wiki/Setting_up_the_Z39.50_and_SRU_Server Note that the community manual is not clear on that point Would it be possible to make SRU available by default in every Koha, whether Zebra or Elasticsearch is used?