  We discuss the emission of $\phi$ mesons with longitudinal and transverse
polarization in ultra-relativistic heavy ion collisions. In the hadronic phase
and in leading order in the kaon diluteness, $\phi$ emission is isotropic and
driven by the flavor singlet and octet vector spectral functions. At next to
leading order, the emissivities receive a non-isotropic correction from the
flavor octet spectral function, and the non-equilibrium contributions
originating from the shear and bulk viscosities. Implications for the $\phi$
meson alignment in heavy-ion collisions are discussed.
