Review of Z' Physics at Future Colliders

We present recent developments in the diagnostic study of heavy gauge bosons at future colliders with the emphasis on the determination of gauge couplings of $Z'$ to quarks and leptons. Proposed diagnostic probes at future hadron colliders are discussed. The study of statistical uncertainties expected for the above probes at the LHC and $M_{Z'}\simeq 1$ TeV shows that three out of four normalized couplings can be determined, thus allowing for a distinction between models. The complementary nature of the probes at future $e^+e^-$ colliders is also discussed.