Flat feet is a foot condition in which the arch of the foot either drops or is never developed. While it is common in babies and small children, it can become a problem if the arch never develops. For adults, the development of flat feet can be brought upon by injury, or may even be a result of pregnancy due to the increased elasticity; however, in adults the flat footedness is usually permanent.

The wet footprint test can be an indicator to diagnosing flat feet. In this test, the individual would place a flat foot on a surface in order to show a footprint. If there is no indentation or indication of an arch, that person may have flat feet. In all cases, it is best to consult a podiatrist if flat feet is suspected or noticed.

Once flat feet has been diagnosed, it can be treated by walking barefoot in beach-like terrain, or wearing insoles. There are two types of flat feet; one being rigid, where the feet appear to have no arch even when the person is not standing, and the other being flexible where the person appears to have an arch while not standing, but once standing the arch goes away. In the case of flexible flat feet, unless there is pain caused by the condition, there is no need for treatment. However, if it causes pain or in the case of rigid flat feet, exercises and orthotic insoles may be prescribed in order to help the arches develop.

In some cases when the condition is severe and all other methods have been exhausted surgery may be required but this is normally avoided due to a lengthy recovery time and high cost.