You can use it alone, but with all the great products they have, you won't!

I only use the product on my lids and under brow and under the eyes. mouth, I use regular face
cream around the area.

When I use it during the day, I don't top it with eye cream as I use a concealer, and don't want my eye area overly moist when I apply that. At night, sometimes I put a little moisturizer over it, but I don't think it really needs it. I have combination skin, but the only oily part is the T-zone.

Use alone, you won't need an eye cream!

I can only report on my experience, which is that it does not seem to alleviate dark circles. Frankly, I am not convinced that anything does, although many products claim to do so. Consequently, I used concealer. It definitely does help with crepiness and sagging, though.

I actually had the opportunity to meet with the founder of Caudalie. I was told that the eye cream (in a white tube) is the one to use for dark circles.

It makes my eyes look much, much less tired, so for me it helps with circles and puffiness, as well as crepiness and sagging.