Betty Den Hollander calibrates the lenses of hundreds of pairs of used eyeglasses received each week by the Niagara Warehouse of Hope. Certain generous optometrists from around the region take working holidays in developing countries, testing villagers' eyesight and prescribing the used eyeglasses.

Under the sponsorship of Lions Eyecare International, Niagara Warehouse of Hopevolunteers calibrate and label tens of thousands of pairs of used eyeglasses for use in the developing world. Cases of these eyeglasses accompany caring optometrists who visit needy countries testing eyesight and distributing the appropriate lenses.