  This review discusses the current status of our knowledge of emission by dust
and molecular gas in high redshift radio galaxies, and the uncertainties in the
derivation of physical parameters from these data. The similarity of
far-infrared luminous, gas-rich high redshift radio galaxies and local
ultraluminous infrared galaxies (ULIGs) is discussed. Given that local ULIGs
rapidly convert most of their gas reservoir into stars, far-infrared luminous
high-z radio galaxies are likely undergoing immense bursts of star formation,
possibly accounting for a large fraction of the final stellar populations in
these systems. These results are discussed in the context of formation
scenarios of massive galaxies.
