  In this paper we will present the \QTR{it}{self-induced approach} to
decoherence, which does not require the interaction between the system and the
environment: decoherence in closed quantum systems is possible. This fact has
relevant consequences in cosmology, where the aim is to explain the emergence
of classicality in the universe conceived as a closed (non-interacting) quantum
system. In particular, we will show that the self-induced approach may be used
for describing the evolution of a closed quantum universe, whose classical
behavior arises as a result of decoherence.
