Closed since 1998, the Victorian hall will be transformed into a new arts, retail and cultural quarter.
Most of the building's original structure, facade and features are to be retained and restored during the regeneration project.
However, a key feature of the scheme is a new copper-clad pavilion which will 'float over a glass-fronted café, bringing life to the top end of the [neighbouring] square.'
The proposals, which are being funded by Barnsley council, will also house the authority's Community Information Service as well as providing assembly rooms for exhibitions, conferences and performances.
In addition, there are plans to brighten up the facade of the hall, which faces The Lanes, with a 'display box of design classics and specially commissioned work'.
The project is due for completion in October next year.