The project investigates the geothermal properties in the southern part of Israel. Properties studied by laboratory and borehole measurements are temperature, thermal conductivity, and radiogenic heat production of the sedimentary formations. From these data, the surface heat flow will be determined and discussed in the context of earlier data from a first reconnaissance study (Eckstein and Simmons, 1978). Furthermore, based on seismic crustal cross sections available through the DESERT and DESIRE activities, a petrological interpretation of the crust and upper mantle will be made. The petrology of the crust then forms the basis for calculating the crustal heat budget. From the heat generated in the crust and from the values of surface heat flow, the mantle heat flow will be determined and interpreted in a lithospheric context. The study also will include a temperature model of the lithosphere, in extension to the models provided for the lithosphere in southern Jordan (Förster et al., 2007, 2010).