  This paper is a continuation of the authors' previous work on noncommutative
joinings, and contains a study of relative independence of W$^*$-dynamical
systems. We prove that, given any separable locally compact group $G$, an
ergodic W$^{*}$-dynamical $G$-system $\mathfrak{M}$ with compact subsystem
$\mathfrak{N}$ is disjoint relative to $\mathfrak{N}$ from its maximal compact
subsystem $\mathfrak{M}_{K}$ if and only if
$\mathfrak{N}\cong\mathfrak{M}_{K}$. This generalizes recent work of Duvenhage,
which established the result for $G$ abelian.
