I consider myself a heavy sleeper, but light will disrupt my sleep every time. Now that it’s summer, light streams into my room at ungodly hours and wakes me up long before I actually have to be awake. Standard curtains I own do a pretty poor job of blocking out light. I took a chance on these and I’m very pleased! My room remains dark and considerably cooler than the rest of the apartment. I have vertical blinds and even when those are pushed back, light is still blocked out. The only light that gets in is at the top and around the sides, but I think that’s pretty unavoidable unless you pin the curtains down. Some light gets in through the bottom for me but that’s only because my window is a little longer than the curtains. Easily remedied, though. I think the cost of these can’t be beat (I bought one blackout curtain panel at Lowe’s for the same price I got this pair). Not as important, but I like the quality and softness of the curtains as well. Worth the purchase for sure!