  Polarized e- and e+ at the International Linear Collider play an important
role for discovering physics beyond the Standard Model and for precisely
unravelling the structure of the underlying physics. The physics programme at
the first energy stage at sqrt{s}=500 GeV benefits strongly from the
polarization of both beams. But also at 1 TeV as well as at a possible
multi-TeV design of a linear collider, CLIC, the physics output is greatly
enriched by beam polarization. An overview is given of the impact of providing
polarized e+ at the linear collider in addition to polarized e- for physics
studies in top, Higgs, supersymmetry and further models of physics beyond the
Standard Model.
