In this paper, we report on the measurement of fluorescence-excitation profiles of Na- D 1 and Na- D 2 lines. The wavelength range used extended from about -3 to +3 cm -1 from the line centre in several premixed, laminar, shielded H 2-O 2-Ar and H 2-O 2-N 2 flames and one C 2H 2-air flame at 1 atm (1400 K ≲ T ≲ 2300 K). We also measured the same profiles in an Na-vapor cell ( T ≈ 460 K) containing Ar, N 2 or H 2 pertubers at p ≈ 0.4 atm to determine the influence of temperature. Using a tunable CW dye laser as excitation source, we determined the fluorescence-excitation profiles by measuring the total fluorescence intensity while tuning the laser wavelength. Comparisons of the shapes of these profiles with a Voigt-profile corrected for hyperfine structure, laser profile and wing-overlap revealed an asymmetry depending on temperature and kind of perturber. The collisional broadening- and shift-rates of the Na- D lines were specified for the main perturbers present in the flames (Ar, N 2, H 2O, and H 2 and compared with the rates measured at much lower temperatures in the cell (Ar, N 2, and H 2 perturbers). For Na-Ar, the broadening- and shift-rates (at T = 500 K and T = 2000 K) were compared with theoretical predictions on the basis of available interaction-potential data. Some modifications had to be made to these potentials to obtain better agreement with experiments. We also measured the absorption profiles of the Na- D 1 and Na- D 2 lines in a λ-range extending from about -4 to +4 cm -1 from the line centres and compared these profiles with the corresponding fluorescence-excitation profiles in two selected flames for which the quantum efficiencies of fluorescence ( Y) differed by a factor of ten. Both profiles proved to be identical within the experimental error of about 5%, as was expected from theory.