The Na-O anticorrelation for individual stars in all confirmed Sgr GCs (plus NGC 4590). For Ter 8, we also show the variation in Na for all the stars with GIRAFFE spectra in the right panel. In the left panel, M 54 (grey empty circles), NGC 4590 (empty squares), and Ter 8 (filled black circles) come from our homogeneous analysis (Carretta et al. 2010c, 2009a,b, and this work, respectively); the abundances of Pal 12 (Cohen 2004, filled red squares) and Ter 7 (Sbordone et al. 2007, open star symbols) have been corrected to our scale of solar abundances (see Gratton et al. 2003). Filled triangles indicate stars of the nucleus of Sgr from Carretta et al. (2010c).