Two parameters are used to assess the maturity of fresh hydraulic cement during the curing process: temperature and water content. This chapter describes the preparation and the application of two optical fiber sensors for simultaneous measurement of temperature and moisture. The temperature sensor utilizes Europium beta diketonates, a luminescent complex with an emission signal that provides temperature data. The moisture sensor utilizes the intrinsic optical properties of the water molecule used for the quantitative measurement of the liquid phase moisture content. These probes were tested in fresh cement paste during the curing processes.