We summarize recent results on the evolution of unpolarized parton densities and deep-inelastic structure functions in massless perturbative QCD. Due to last year's extension of the integer-moment calculations of the three-loop splitting functions, the NNLO evolution of the parton distributions can now be performed reliably at momentum fractions x approx> 10~(-4), facilitating a considerably improved theoretical accuracy of their extraction from data on deep-inelastic scattering. The splitting-function series converges rapidly at large x, hence, employing results on the three-loop coefficient functions, the structure functions can be analyzed at N~3LO for x > 10~(-2). The resulting values for α_s do not significantly change beyond NNLO, their renormalization scale dependence reaches about +-1% at N~3LO.
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