Today, Photonics is considered by the European Commission a Key Enabling Technology (KET) for the Europe Development and also an Essential Technology for the Nation (USA). Photonic Sensing understood in wide sense as “sensing using light technologies” will be and area with very important expectations of annual growths and strong socio-economic impacts in the present decade (2010-2020). In the talk, after a mention of what it must be understood as Photonics field we will go into Photonic Sensing area including the particular case of the sensors using fiber technologies (OFS). Several significant cases (including the ones useful for geotechnical applications) will be presented and discussed.