Comparison of Diagnostic Z' Physics at Future pp and e+e- Colliders

We present recent developments in the diagnostic study of heavy gauge bosons at future $pp$ (CERN LHC) and $e^+e^-$ (NLC) colliders with the emphasis on the model independent determination of gauge couplings of $Z'$ to quarks and leptons. The analysis reflects a complementary diagnostic power of the LHC and the NLC (c.m. energy 500 GeV, integrated luminosity 20 fb$^{-1} $). At the NLC for $M_{Z'} \sim 1 $ TeV {\it all } the quark and lepton charges can be determined to around $10-20 \%$, provided heavy flavor tagging and longitudinal polarization of the electron beam is available. At the LHC primarily the magnitude of three (out of four) normalized couplings can be determined, however typical uncertainties are by a factor $\sim 2$ smaller than at the NLC.