Confused? You aren’t alone! Serums are a reasonably new addition to the skin care market which mutually (but not exclusively) herald as moisturisers, actives and exfoliants all in one!

A serum itself is usually, liquid, transparent or milky, and of more highly concentrated substances than most other products. They also tend to have more stabilised ingredients with a lower molecular weight that are able to penetrate the skin barrier more readily than say a night cream.
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For these qualities serums are often useful for targeting specific skin concerns such as dehydration, acne, redness, sensitivity, pigmentation…. And are handy for boosting the efficacy of your skin care regime.
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So how are they used?
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Serums are applied topically to the skin, focusing on areas of concern – often application is full face. Frequency and timing will depend on your skin, but also the active ingredients in the serum – for example, vitamin A (retinoic acid) should usually only be applied of an evening.

In terms of sequencing, depending on the properties and viscosity of your serum will depend on when in your regime it is applied. In my own routine, if I am unsure, I usually start with thinnest product first or let products completely absorb before putting the next one on… and sunscreen is always last. But generally, water based serums are useful prior to moisturiser, and oil based (with a larger molecule) on top of moisturiser to help occlude products onto the skin.