  We discuss the influence of a uniform current, $\vec{j} $, on the
magnetization dynamics of a ferromagnetic metal. We find that the magnon energy
$\epsilon(\vec{q})$ has a current-induced contribution proportional to
$\vec{q}\cdot \vec{\cal J}$, where $\vec{\cal J}$ is the spin-current, and
predict that collective dynamics will be more strongly damped at finite ${\vec
j}$. We obtain similar results for models with and without local moment
participation in the magnetic order. For transition metal ferromagnets, we
estimate that the uniform magnetic state will be destabilized for $j \gtrsim
10^{9} {\rm A} {\rm cm}^{-2}$. We discuss the relationship of this effect to
the spin-torque effects that alter magnetization dynamics in inhomogeneous
magnetic systems.
