Abstract: An assembly of interlaced rods, suitable for use as embedded reinforcement in matrix materials, comprising first, second and third layers of rods, the rods of each layer being orientated generally parallel to one another, the second layer being located between the first and third layers, the rods of the first and third layers being longitudinally orientated in the same direction, with those of the second layer being longitudinally orientated generally at right angles thereto, the rods of the first and third layers being paired such that each nth rod of the first layer, herein designated rod n1, is paired with the nth rod of the third layer, herein designated rod n3, paired rods of the first and third layers being drawn together under tension by a flexible filament wound between them in a series of runs each comprising a forward and reverse sinusoidal winding which interlaces rods of the first and third layers, whereby each pair of rods n1 and n3 in the first and third layers is enclosed by and drawn together