In free probability theory, the mutual free information is defined as the amount of time required for a stochastic time evolution called the liberation process to render two noncommutative random variables free. In this talk, I'll describe a quantum mechanical version of the liberation process and find that the time it takes to decouple two quantum systems is precisely the familiar quantum mutual information defined in terms of the von Neumann entropies of the state. In contrast, no formula for the mutual free information in terms of the free entropy is known.