Myopia is a major health problem throughout the world due to its increasingly high prevalence in the past few decades. Myopia, in particular high myopia, is associated with a number of ocular complications such as glaucoma and cataract that are potentially blinding. Myopic macular degeneration, a major cause of visual impairment and blindness, affects 1–4% of the general populations in some countries. Increased amount of near-work activities and decreased time spent outdoors are the two most important environmental modifiable risk factors related to myopia onset and progression. Near-work activities including screen time with use of smartphones and devices might be a new major risk factor for myopia. Combining health behavior programs aiming to increase outdoor time and decreasing screen time may prevent the onset of myopia. Interventions to slow the progression of low myopia to high myopia may prevent severe disease and associated pathological myopia complications.