We present abundance ratios for 23 elements with respect to Fe in a sample of stars with a wide range in luminosity from luminous giants to stars near the turnoff in a globular cluster .
Our sample of 25 stars in M71 includes 10 giant stars more luminous than the red horizontal branch ( RHB ) , 3 HB stars , 9 giant stars less luminous than the RHB , and 3 stars near the turnoff .
The analyzed spectra , obtained with HIRES at the Keck Observatory , are of high dispersion ( R= \lambda / \Delta \lambda =35,000 ) .
We find that the neutron capture , the iron peak and the \alpha - element abundance ratios show no trend with T _ { eff } , and low scatter around the mean between the top of the RGB and near the main sequence turnoff .
The \alpha - elements Mg , Ca , Si and Ti are overabundant relative to Fe .
The anti-correlation between O and Na abundances , observed in other metal poor globular clusters , is detected in our sample and extends to the main sequence .
A statistically significant correlation between Al and Na abundances is observed among the M71 stars in our sample , extending to M _ { V } = +1.8 , fainter than the luminosity of the RGB bump in M5 .
Lithium is varying , as expected , and Zr may be varying from star to star as well .

M71 appears to have abundance ratios very similar to M5 whose bright giants were studied by Ivans et al . ( 40 ) , but seems to have a smaller amplitude of star-to-star variations at a given luminosity , as might be expected from its higher metallicity .
Both extremely O poor , Na rich stars and extremely O rich , Na poor stars such as are observed in M5 and in M13 are not present in our sample of M71 stars .

The results of our abundance analysis of 25 stars in M71 provide sufficient evidence of abundance variations at unexpectedly low luminosities to rule out the mixing scenario .
Either alone or , even more powerfully , combined with other recent studies of C and N abundances in M71 stars , the existence of such abundance variations can not be reproduced within the context of our current understanding of stellar evolution .