Neck firming cream needs to be richer than a face cream, because neck skin is thinner and has fewer oil glands. Karin Herzog's neck routine pairs the E&R Pro Booster serum with Vita-A-Apricot, a nourishing vitamin A cream with 2% active oxygen, for crepey, loose-looking skin.

How to use it: apply the serum first, then the cream. Sweep upward from the collarbone to the jaw, morning and night. Most people notice softer, more hydrated skin first; texture and the look of lines improve over several weeks.

Sensitive skin? Start with Vita-A-Kombi 1% and add the serum later. More tips in our neck firming guide.