  In this talk we summarize main results of a recent determination of the
polarized deeply inelastic parton distributions to NLO from the world data. In
the analysis the LO and NLO parton densities and their $1\sigma$ statistical
errors were derived and parameterized. The strong coupling constant
$\alpha_s(M_Z^2)$ is determined $\alpha_s(M_Z^2) = 0.113 \pm 0.004 {\rm
(stat.)} \pm~0.004 {\rm (fac.)} +0.008/-0.005 {\rm (ren.)}$ Comparisons of the
low moments of the parton densities with recent lattice results are given. A
detailed error-analysis of the gluon density is performed.
