Kinetic equations for long-wavelength excitations of the quark-gluon plasma

We show that long-wavelength excitations of the quark-gluon plasma are described by simple kinetic equations which represent the exact equations of motion at leading order in g. Properties of the so-called ``hard thermal loops,'' i.e., the dominant contributions to amplitudes with soft external lines, find a natural explanation in this approach. In particular, their generating functional appear here as the effective action describing long-wavelength excitations of the plasma.