Mirrors are an important component to the architectural design of interior and exterior applications for residential, commercial, and industrial settings. Through its reflective qualities, a well-placed mirror can bring light into the living space as well as provide a feeling of enlarging the space around you. However, reflective images from the mirror may exhibit slight distortion, which is a function of the glass used to fabricate the mirror or the result of the mirror installation. The Technical Services Division of the National Glass Association (NGA) has produced this Glass Technical Paper solely for informational purposes. This Paper was developed by dedicated member volunteers and subject matter experts. This document was originally published in 2015. This version of the document was updated and published in April 2023.