When we imagine a beauty routine, chances are, the phrase conjures thoughts of cleanser, retinol, sunscreen, and maybe a serum or two. But thanks to an area of the beauty world I like to think of as “gadgetry,” everyday routines are expanding to include high-tech treatments that were previously only available in a professional’s office. This category includes at-home laser hair removal, personal microcurrent treatments, and, increasingly, at-home LED light therapy.

Although these devices can have a slight Westworld feel, companies like tried-and-true Neutrogena and device specialists like Dr. Dennis Gross have come out with light therapy tools that claim various skin benefits. But does at-home light therapy really work? And what does it do, anyway? Before you get started on your RoboCop impression, we asked board-certified dermatologists to break down exactly what you need to know about light therapy.