  We consider the effect of stochastic fluctuations of the gravitational
coupling G on the evolution of binary systems. We work at an elementary level,
in the Newtonian limit, and focusing mainly on laser ranging. We show that, due
to cumulative effects, observational data may be used to put bounds on the
stochastic fluctuations. We also reanalyse previous results on the implications
of stochastic fluctuations of G on cosmological models.
