  We discuss the possibility of having "quantum dissipation" due to the
interaction with chaotic degrees of freedom. We define the conditions that
should be satisfied in order to have a dissipative effect similar to the one
due to an interaction with a (many body) bath. We also compare with the case
where the environment is modeled by a random matrix model. In case of
interaction with "chaos" we observe a regime where the relaxation process is
non-universal, and reflects the underlaying semiclassical dynamics. As an
example we consider a two level system (spin) that interacts with a two
dimensional anharmonic oscillator.
