The improvement of stratum corneum hydration is one of the most important claims in the cosmetic industry. Most commercially available methods are based on measuring skin impedance and capacitance in vivo in clinical tests. These are indirect measures of skin moisture levels and have to be used very carefully to avoid experimental artefacts. At TRI, skin moisture content can be measured reliably and semi-quantitatively using spectroscopic techniques. TRI offers a variety of spectroscopic skin moisture tests, including ATR-FTIR imaging and Confocal Raman imaging. Our portable FTIR optical probe (Remspec) can be used in pre-clinical tests at TRI, or in clinical tests (in partnership with clinical testing companies) to measure moisture levels in the stratum corneum, across a wide range of body sites.