  In this paper we present a Next-to-Next-to Leading Order (NNLO) calculation
of the production of a Higgs boson in association with a massive vector boson.
We include the decays of the unstable Higgs and vector bosons, resulting in a
fully flexible parton-level Monte Carlo implementation. We also include all
$\mathcal{O}(\alpha_s^2)$ contributions that occur in production for these
processes: those mediated by the exchange of a single off-shell vector boson in
the $s$-channel, and those which arise from the coupling of the Higgs boson to
a closed loop of fermions. We study final states of interest for Run II
phenomenology, namely $H\rightarrow b\bar{b}$, $\gamma\gamma$ and $WW^*$. The
treatment of the $H\rightarrow b\bar{b}$ decay includes QCD corrections at NLO.
We use the recently developed $N$-jettiness regularization procedure, and study
its viability in the presence of a large final-state phase space by studying
$pp\rightarrow V(H\rightarrow WW^*) \rightarrow$ leptons.
