A device for stabilising a ladder against a surface, the ladder having a pair of stiles and a plurality of rungs connected therebetween, the device comprising: an engagement mechanism for releasably engaging two adjacent rungs, the engagement mechanism including two opposed receiving portions for at least partially receiving a rung, at least one of the receiving portions being selectively movable relative to the other thereby allowing the engagement mechanism to urge against the adjacent rungs; and at least one arm pivotably connected to the engagement mechanism to allow pivoting thereof to a fixed angle relative to the engagement mechanism, the at least one arm having an abutting portion for abutting under the surface, thereby allowing the ladder to be wedged between the surface and ground level to stabilise the ladder.