  We present the results of a global analysis of a class of models with an
extended electroweak gauge group of the form SU(2) x SU(2) x U(1), often
denoted as G(221) models, which include as examples the left-right, the
lepto-phobic, the hadro-phobic, the fermio-phobic, the un-unified, and the
non-universal models. Using an effective Lagrangian approach, we compute the
shifts to the coefficients in the electroweak Lagrangian due to the new heavy
gauge bosons, and obtain the lower bounds on the masses of the Z' and W'
bosons. The analysis of the electroweak parameter bounds reveals a consistent
pattern of several key observables that are especially sensitive to the effects
of new physics and thus dominate the overall shape of the respective parameter
contours.
