Uncorrected refractive error accounts for half of the global burden of avoidable vision impairment and nearly a third of the global burden of avoidable blindness.1 2 Globally, 153 million people have visual impairment or are blind due to uncorrected refractive error and the majority live in low income countries.1 Additionally, 410 million people have difficulty with near tasks because they lack reading glasses.2 Interventions to treat refractive error, such as spectacles, are cost-effective and in high income settings are readily accessible, but refractive errors are often not diagnosed or referred and barriers to the use of services exist.1 Under-corrected refractive error can account for as much as 75% of all impairment of vision in high income countries 1 3 4 5 and it may markedly affect quality of life.5 Minor reduction in vision (<6/12 or just below the driving standard) has been associated with an increased risk of death and physical, social, and psychological problems in people older than 50 years (box 1).6 w1-7 The global economic impact of uncorrected refractive error is an estimated 268.8 billion international dollars, based on population and economic data combined with a meta-analysis of prevalence studies.7 We provide an overview of the public health significance of refractive error, its management, and referral strategies for primary care practitioners. #### Box 1 Consequences of minor vision impairment (<6/12) in people older than 50 years ##### Increased social isolation ##### Increased morbidity ##### Increased mortality #### Sources and selection criteria In October 2008 and May 2009 we searched the Cochrane Collaboration database for reviews and clinicaltrials.gov for current trials, returning 420 studies. We also searched Medline and PubMed for articles published between 1 January 2000 and 1 May 2009, using MESH terms and combinations including …