The theory of characters of wreath products of finite groups is very w
ell known. The basic fact is that any invariant irreducible character
of the base group is extendible to the wreath product, and an extensio
n can be computed explicitly. In this paper we shall study the charact
er table of a wreath product as a whole, rather than single characters
. We shall prove that the character table of a wreath product G \ A is
determined uniquely by the permutation group A and the character tabl
e of G. This result provides a powerful tool for increasing the derive
d length of a group, while keeping its character table under control.
We shall employ it in Section 4 to construct pairs (G, H) of groups wi
th identical character tables and derived lengths n and n + 1, for any
given natural number n greater than or equal to 2. (C) 1995 Academic
Press, Inc.