A one-piece plastics material mesh structure, particularly a geogrid, is produced by stretching a plastics sheet starting material formed with an array of holes and comprises a plurality of generally parallel rib structures extending longitudinally in a first direction parallel to the stretch direction and a plurality of generally parallel bar structures extending in a second direction transverse to the rib structures. The rib structures and said bar structures are interconnected by junctions. The rib structures have rib segments oriented in the first direction along their lengths and orientation in this direction extends across the junctions connecting two such oriented rib segments. The bar structures are such that their overall stretch ratio in the second direction is a maximum of 1 and all locations along the length of the bar structures have a maximum orientation of 1.5 in the second direction.