Spin tracking at the international linear collider

Polarized e - and e + beams are foreseen for the future International Linear Collider (ILC). High precision physics requires the polarization of both beams to be known with a relative uncertainty of about 0.1% or better. Therefore all possible depolarizing effects that could operate between the polarized sources and the interaction regions have to be under full control. This report gives a brief summary of ongoing work on the ILC spin-dynamics concentrating on recent results for depolarizing effects in the ILC damping rings, main linac, beam delivery system and beam-beam interactions. The polarization dependence of incoherent and second order coherent background processes have been taken into account as well as the treatment of spin precession in strong fields.