Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising combinations of reinforcements, {e.g. non-specified reinforcements, fibrous reinforcing inserts} and fillers, {e.g. particulate fillers}, incorporated in matrix material, forming one or more layers and with or without non-reinforced or non-filled layers {and with one or more layers of non-plastics material or non-specified material, e.g. supports}