Electroweak physics at the ILC

Some aspects of electroweak physics at the International Linear Collider (ILC) are reviewed. The importance of precision measurements in the Higgs sector and in top-quark physics is emphasized, and the physics potential of the GigaZ option of the ILC is discussed. It is shown in particular that even in a scenario where the states of new physics are so heavy that they would be outside of the reach of the LHC and the first phase of the ILC, the GigaZ precision on the effective weak mixing angle may nevertheless allow the detection of quantum effects of new physics.