The town of Olsberg provides financial and non-material support for the work of associations, cultural organisations and independent cultural work. It supports the local and town heritage organisations and the Olsberg Heritage Association.
The town of Olsberg is twinned with the following towns:
- City of Fruges / France since 3 May 1969 (friendship pledge with the municipalities of the district of Fruges dated 28 August 2010)
- Municipality of Olsberg / Switzerland since 06/07/1972
- City of Jöhstadt / Saxony since 31/08/1990