  A subset S of a group G invariably generates G if G = <s^(g(s)) | s in S> for
each choice of g(s) in G, s in S. In this paper we study invariable generation
of infinite groups, with emphasis on linear groups. Our main result shows that
a finitely generated linear group is invariably generated by some finite set of
elements if and only if it is virtually solvable. We also show that the
profinite completion of an arithmetic group having the congruence subgroup
property is invariably generated by a finite set of elements.
