  We generalize the peak-reduction algorithm (Whitehead's theorem) for free
groups to a theorem about a general right-angled Artin group A_Gamma. As an
application, we find a finite presentation for the automorphism group Aut
A_Gamma that generalizes McCool's presentation for the automorphism group of a
finite rank free group. We also give consider a stronger generalization of
peak-reduction, giving a counterexample and proving a special case.
