The prevalence of myopia in Singapore is among the highest in the world, with 65 percent of our children being myopic by Primary 6, and 83 percent of young adults being myopic. As such, Singapore is often labelled as the Myopia Capital of the World. By 2050, it is projected that 80 to 90 per cent of all Singaporean adults above 18 years old will be myopic and 15 to 25 percent of these individuals may have high myopia. High myopia (spherical equivalent refraction ≤ -5 D) puts one at risk of many eye disorders later in life, such as early cataracts, glaucoma and macular degeneration. These complications often cause significant morbidity and may even be sight-threatening. Hence there is an urgent and growing need for synergistic efforts to counter myopia. The goal of this clinical trial is to test the efficacy of spectacle lenses in controlling the progression of myopia in children (aged 6-12 years) over a period of 2 years. In addition, this trial aims to evaluate the impact of these spectacle lenses on central visual performance and visual comfort. Therefore, in this randomised, double-masked clinical trial, one hundred and eighty-five (n=185) subjects aged 6-12 years with mild or moderate myopia (\< -5D) will be randomised in a 1:1 allocation ratio into three strata defined by age 6-8, 8-10 and 10-12 years to ensure age balance between the two arms (control group - single vision lenses and intervention group - myopia control lenses, gender matched). In the control group, after one year (12 months) of wearing single vision lenses, the children will switch to the myopia control lenses (crossover design).