  We present and discuss the results of an experimental analysis in the design
of Boolean networks by means of genetic algorithms. A population of networks is
evolved with the aim of finding a network such that the attractor it reaches is
of required length $l$. In general, any target can be defined, provided that it
is possible to model the task as an optimisation problem over the space of
networks. We experiment with different initial conditions for the networks,
namely in ordered, chaotic and critical regions, and also with different target
length values. Results show that all kinds of initial networks can attain the
desired goal, but with different success ratios: initial populations composed
of critical or chaotic networks are more likely to reach the target. Moreover,
the evolution starting from critical networks achieves the best overall
performance. This study is the first step toward the use of search algorithms
as tools for automatically design Boolean networks with required properties.
