  The [O II] 3727 line, a commonly used estimator of star formation rate in
extragalactic surveys, should be an equally effective tracer of star formation
in the host galaxies of quasars, whose narrow-line regions are expected to
produce weak low-ionization emission. Quasar spectra generally show little or
no [O II] emission beyond that expected from the active nucleus itself. The
inferred star formation rates in optically selected quasars are typically below
a few solar masses per yr, and some significantly less. Quasars do not appear
to occur coevally with starbursts. Recent observations, on the other hand,
reveal abundant molecular gas in low-redshift quasars. These two results
suggest that the star formation efficiency in quasar host galaxies is somehow
suppressed during the active phase of the nucleus. The low star formation rates
also imply that the nonstellar nucleus powers the bulk of the thermal infrared
emission in radio-quiet quasars.
