  The families of characters, defined by Lusztig for Weyl groups, play an
important role in the representation theory of finite reductive groups. The
definition of Rouquier for the families of characters in terms of blocks of the
Hecke algebra has made possible the generalization of this notion to the case
of complex reflection groups. In this article, we study the Rouquier blocks of
the cyclotomic Hecke algebras and we show that they depend on numerical data
determined by the generic Hecke algebra. Moreover, we provide the algorithm and
the results of their determination for all exceptional complex reflection
groups.
