Does not work instant if at allIt works!I've been using MAC Fast Reponse Eye Cream since the day it arrived in my mailbox. I have very noticeable dark bags under my eyes and nothing had helped in any way until I received the MAX Fast Response. I actually notice a difference in the degree of darkness under my eyes - they are getting lighter by the day. I use it twice a day and also wear it under my makeup. It makes my skin feel softer and my bags seem smaller already. I'm pretty sure the container will last me a few months and when it gets low, I will order another one right away. This is the only product that has ever done anything at all to my dark under eyes. I am so relieved I found this eye cream.I have used this product and recommended it to friends for the past decade. While it does have a higher price tag, it is worth every single penny. I normally go through about one tube every three months and stock up on it while it's on sale. The caffeine works quickly to "depuff" the eyes and increase circulation while the formulation leaves the skin firm, smooth and ready for makeup application.Love this stuff. Best eye cream out therrIt works for the moment and it is hard to apply make up on top of it. If you apply it and put on make up it makes your dark circles more visible. I gave it 3 stars because it goes on so smooth and feels really good on your skin. I wouldn't recommend it because it doesn't make the dark circles go away. I have been using it for 45 days and I have not seen any results. If anyone finds something that works for dark circles, please share!!!!!I love that only a little comes out at a time and its perfect for the under eye area - I don't really have need for this yet but I use it nightly with my face lotionI hope to have this on monthly auto c renewal