In this paper we present the first results of the analysis of intermediate resolution ( \Delta \lambda \sim 3.5 \AA ) spectra of giants of the Sagittarius dwarf galaxy acquired using the ESO NTT telescope .
From the deep CCD photometry of Marconi et al ( 1998a ) we have selected a sample of giants representative of the metallicity spread suggested by the comparison of the colour-magnitude diagram of Sagittarius with those of galactic globular clusters .
The spectra have been used to measure radial velocities , to confirm the membership to Sagittarius , and to provide a metallicity estimate by using spectral synthesis techniques .
The analyzed stars show a spread in metallicities in the range -1.0 \leq [ Fe / H ] \leq + 0.7 , some 0.5 dex more metal-rich than the photometric estimates .