Let A be a group of automorphisms of the finite group G such that (\A\
, \G\) = 1. Then \A\ < \G\(2), and the exponent 2 here is best possibl
e. If, moreover, A is nilpotent of class at most 2, then \A\ < \G\. If
A is abelian, then A has a regular orbit on G.