 Recent results on animal models of myopia suggest that the eye has the ability to detect the overall sign of defocus of images falling on the retina, with myopic defocus imposed by the fitting of plus-lenses halting or slowing axial elongation of the eye. In the animal models, these STOP growth signals have been shown to be particularly strong - with brief periods of high myopic defocus able to outweigh the effects of prolonged periods of imposed hyperopic defocus in promoting eye growth. These results therefore suggest a novel strategy for preventing the progression of myopia in children - the imposition of high levels of myopia for brief periods of time. This approach is conceptually distinct from under-correction, which imposes chronic mild myopic defocus. 