I have deep, hollow undereyes that never EVER look fully concealed. I've tried it all!!!!!!!!! This is pretty cool stuff. I'm still figuring out application but I've been doing it the exact same way the founder does it on her social media. Light, thin layers that are painted on without a heavy hand but are strategic and I feel like this highlighter refracts the blue, hollows in such a nice way. It doesn't erase them completely--nothing will except invasive procedures-- but it does soften them ALOT. Also, covering them is almost impossible without it looking cakey or highlighting them even more. I feel like this stuff is what the Kosas concealer is trying to be but this does it better. There's more dimension to the covering of the hollows because of the shimmer and the yellow color. If you're expecting this to look like you have a whole new undereye--sorry, babe. Nothing can fix that. But if you want to work with what you have and think about your circles as something to refract light away from...then this is for you. I think I'll be using this for a really long time! Thanks!