After 4 weeks of using this serum with the rest of the Clarins Bright Plus range I must say my complexion is more radiant, and the dark patches and spots are reduced. I saw a difference in my complexion on the 2nd week of using the range, however my problem areas (Hyper pigmentation) which are my cheeks, mouth and chin area became darker or the the darkness was more visible. As a result I am using the serum only on those areas now and my skin is starting to even out. A plus for me is that it did not break out my very sensitive skin . I am sure with continued use my skin will be completely evened out.