  An important question to be addressed regarding system control on a time
interval $[0, T]$ is whether some particular target state in the configuration
space is reachable from a given initial state. When the target of interest
refers only to a portion of the spatial domain, we speak about regional
analysis. Cellular Automata (CA) approach have been recently promoted for the
study of control problems on spatially extended systems for which the classical
approaches cannot be used. An interesting problem concerns the situation where
the subregion of interest is not interior to the domain but a portion of its
boundary. In this paper we address the problem of regional controllability of
cellular automata via boundary actions, i.e., we investigate the
characteristics of a cellular automaton so that it can be controlled inside a
given region only acting on the value of sites at its boundaries.
