[en] The physics potential of e⁺e^- linear colliders is briefly summarized in this report. These accelerators are expected to operate in the first phase at an energy of 500 GeV which will be upgraded adiabatically to about 1 TeV; in the second phase a maximum energy of 1.5 to 2 TeV should be reached finally. The machines will enable us to perform precision studies of the top quark and the electroweak gauge bosons in the Standard Model. They are ideal instruments to search for Higgs particles and to explore their characteristic properties. In the area beyond the Standard Model, new particles and interactions can be searched for. In particular, these accelerators provide unique opportunities for investigating supersymmetric particles and the structure of the underlying theory. The programme of e⁺e^- linear colliders is largely complementary to the programme of the pp collider LHC. By operating both types of machines the physics in the range above the existing machines up to the TeV region can be explored in a conclusive way. (orig.)