  We consider the combined effects of a power law L\'{e}vy step distribution
characterized by the step index $f$ and a power law waiting time distribution
characterized by the time index $g$ on the long time behavior of a random
walker. The main point of our analysis is a formulation in terms of coupled
Langevin equations which allows in a natural way for the inclusion of external
force fields. In the anomalous case for $f<2$ and $g<1$ the dynamic exponent
$z$ locks onto the ratio $f/g$. Drawing on recent results on L\'{e}vy flights
in the presence of a random force field we also find that this result is {\em
independent} of the presence of weak quenched disorder. For $d$ below the
critical dimension $d_c=2f-2$ the disorder is {\em relevant}, corresponding to
a non trivial fixed point for the force correlation function.
