The optical properties of lead and europium doubly doped NaCl single crystals have been analyzed. It is found that energy transfer not only occurs from the Pb2+P1 level to the 4f6 5d (t2g) state of the Eu2+ ions, but also from the 4f6 5d (eg) state of Eu2+ to the 3P1 level of the lead ions. This transfer is observed in samples which have been quenched from high temperatures, as well as for low impurity concentration. The results obtained suggested that the energy transfer occurs between Pb-Eu close pairs. In order to get a better insight into this point, electron paramagnetic resonance measurements were also performed in parallel with the optical ones. The analysis of the Eu-EPR spectra shows that the site symmetry normally occupied by the Eu2+ ions in NaCl is strongly modified by the presence of perturbing neighboring lead ions.