  We review the recent glueball mass calculations using an efficient method for
solving the Schr\"odinger equation order by order with a scheme preserving the
continuum limit. The reliability of the method is further supported by new
accurate results for (1+1)-dimensional $\sigma$ models and (2+1)-dimensional
non-abelian models. We present first and encouraging data for the glueball
masses in 3+1 dimensional QCD.
