Visual Stress assessment should be carried out for all weak readers by the end of key stage one. The visual stress assessment pack is the ideal tool, as the assessment can be carried out by non-specialists and will identify the children (5%, or around ten in every average-sized primary school), whose reading is severely impeded by distorted print or other symptoms. Lucid VISS software is ideal for identifying visual stress in older readers. The children who just need a reading ruler or coloured overlay to increase their reading speed by 25% or more can be quickly identified with the Visual Stress Assessment Pack.