The principle is simple: find an old photograph of yourself or someone in your family, and then repeat the pose in as precise a manner as you can.
Some of the results, a compilation of which are about to published in a new book, are laugh-out-loud funny. Others are poignant reminders of how much people change - and how much they stay the same.
We've picked out some of our favorites from the book, alongside commentary by the people featured in the photographs.
Is there a photograph from your own childhood that you would want to replicate? Tell us about it in the comments.