Chipmunk mentions Sisley. Everyone to their own, but I must stick up for this brand which, for me, is the best. It is very expensive, but I do love their products - particularly SisleyA, their top of range moisturiser for mature skins, and their excellent Express Flower Gel mask - and I do believe that my skin has benefited from them. Though of course I accept this may not be a wholly rational belief, because it's very difficult to 'prove' that it's any one product you put on your skin which is making the difference. So many other factors come in.

Alas, now I'm not in paid work but a student I can't really afford Sisley so at present am using a mix of Liz Earle, Clarins, and Boots (Protect and Perfect serum, Uplifting day cream) and the results do seem satisfactory. But I still miss the texture, smell, and ease of absorption of SisleyA. (I also use Imedeen, or the cheaper Boots equivalent, and drink lots of water).