Buying glasses with the correct lenses can be expensive - but it doesn't have to be this way.

A film for BBC World Hacks by Lucy Ashton and Richard Kenny. Like, Share, Engage.

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Correction 11 July 2018: This page and video have been amended to correct a statistic that was out of date. According to The Medical Council of Malawi there are now 49 registered optometrists in Malawi, and not 17 as was originally stated.