Abstract: In mining the hanging wall is supported by pillars comprising a particulate backfill material which has been consolidated so that it has at the most one quarter voids by volume. Layers of reinforcing material are provided in the backfill to take horizontal loads associated with vertical loads being taken by the pillars in supporting the hanging wall. The pillars extend back from a work space behind the work face transversely to the work face. They are spaced in a direction along the workface and their loading ends advance as the work face advances.