I'm very fond of this product. Absolutely a great value! I waited six weeks before posting a review as to give this product time to do it it's magic. Before using the product, I read the reviews which are all very helpful and I did some additional research of my own. First of all, I would say that how you apply it is very important.Initially you will experience a redness and a bit of irritation which is completely normal that means that the product is working. The first couple weeks I used the retinol every other day to minimize the redness . I think this is something that varies from individual and you need to determine how often is best for your skin.I have found the optimal results to be as follows ...In the morning, I wash my face in the usual manner and pat my face dry leaving it damp then I apply Hyaluronic acid for plumping and firming of the face, Followed by my morning moisturizerIn the evening I wash my face again in my usual manner, pat my face dry leaving it damp, then I apply vitamin C followed by the retinal . ( at first you may want to alternate vitamin C one day and retinol the next) don't forget to include the lower lids neck and chest.Once the serum has dried I apply vitamin E Oil, (research has shown that vitamin E oil is a great complement when you sing vitamin C and retinal) last I apply my night moisturizer.I am years old and have fairly good skin. What I struggled with was Sun damage, uneven skin tone and fine lines. In six weeks I have already noticed a difference in diminished dark spots from sun damage almost completely gone. The skin tone is even and glowing I don't feel the need to wear make up on a regular basis anymore.Overall, I'm very impressed with this product and I will continue to use it for one year as my research yields that after one year you should get a stronger strength retinol serum.