We have determined the theoretical predictions for the cross sections
of squark and gluino production at p (p) over bar and pp colliders (Te
vatron and LHC) in next-to-leading order of supersymmetric QCD. By red
ucing the dependence on the renormalization/factorization scale consid
erably, the theoretically predicted values for the cross sections are
much more stable if these higher-order corrections are implemented. If
squarks and gluinos are discovered, this improved stability translate
s into a reduced error on the masses, as extracted experimentally from
the size of the production cross sections. The cross sections increas
e significantly if the next-to-leading order corrections are included
at a renormalization/factorization scale near the average mass of the
produced massive particles, This rise results in improved lower bounds
on squark and gluino masses. By contrast, the shape of the transverse
-momentum and rapidity distributions remains nearly unchanged when the
next-to-leading order corrections are included. (C) 1997 Elsevier Sci
ence B.V.