Strong interactions of weak bosons

We discuss the parameterization for electroweak gauge boson interactions without a light Higgs boson. We present the constraints on the anomalous gauge-boson couplings from the current experiments. We emphasize that the four-point couplings involving the longitudinal weak bosons are genuine to the underlying strong dynamics responsible for the electroweak symmetry breaking. We study the sensitivity to the four-point couplings and the possible heavy resonant states in this sector at future TeV $e^+e^-$ linear colliders.