Process for the selective targeting of sebaceous glands

A method for selectively directing the sebaceous glands to effect a desired non-surgical treatment, said method comprising: irradiating said sebaceous glands with optical radiation at a wavelength for which the absorption coefficients for oil and water have a ratio that is at least 0.5, wherein the radiation fluence and for a sufficient duration for the desired treatment, wherein said wavelength is in a band that is one of: (a) from 1690 to 1780 nm, preferably 1700 nm to 1730 nm, more preferably 1715 nm; and (b) of 2250 nm to 2450 nm, preferably 2360 nm to 2280 nm, 2300 nm more preferably.