Does this lighten up to 30% Yes! It does work, and it is worth the money. A few things I think people should know about this product- #1 the product is oil free, but it feels like a slippery silicone primer on the skin. You cannot apply your foundation/concealer/powder right away with this product, you must let it dry first. I am able to use concealer on top of this eye treatment without it creasing. #2 the color is a tinted salmon/orange/flesh tone. I first made the mistake of using a grain of rice size amount on my pale skin. It looked obviously orange and I would not have been able to throw this on and walk out of the house without makeup on top to conceal the orange. I have learned to use a pin head size amount for best results. The orange based color really does help to counteract purple/gray/dark circles. If you don't like to wear makeup or you are a man, you may want to experiment with how much you can use without having to apply a neutral concealer on top. If you have light under eye circles you could use this product as a concealer. I am about nc15-nc20 for reference. Those of you with medium skintone may not even notice the orange tint to the product..I think the description from clinique.com is misleading, it says it uses "sheer optics" when it should say a tinted orange or warm tone so people will know there is color pay off with this, not like your average brightener. I have been using this for 20 days now and I can honestly say my under eye area is so much brighter. This product claims to lighten up to 30% in 12 weeks and it works! Please note, I do not have hereditary dark brown circles. I have purple/gray circles from allergies. This product is supposed to build & thicken the under eye skin so the color doesn't show through as much. It works for my allergy induced circles, I cannot comment on its affects on brown discoloration under the eye. The silver metal end of this product is flat and makes it super easy to rub the product on. The metal also makes it feel very cooling to the under eye area. I can say this worked much better than dermadoctor's eye balm that gets great reviews on here, its a few dollars cheaper too. Try a sample. Not only does it temporarily conceal & help your eye look over all, but it physically worked to lighten my under eye circles. I cannot wait to finish my tube, and to repurchase. Buy it! ...This review has been edited a few times since my initial purchase. jan /2013 update I am still loving this product & continue to repurchase it. It did lighten my circles by 30% & it helped a ton with concealing. I do have allergy circles vs hereditary so that may make a difference. It has not lightened beyond 30% with me, but I also rotate it with a moisturizing eye cream. This is strictly for my under eye area, and my other creams I use on my eye lid as well as the under eye area. Clinique is great with refunds, use this faithfully morning & night & let it dry before you wipe your eye area. You should see results!