Experimental Issues for Precision Electroweak Physics at a   High-Luminosity Z Factory
  We discuss the ultimate precision for ALR, and therefore for the weak mixing angle, at a high-luminosity Linear Collider. Drawing on our experience at the SLC, and considering various machine parameter sets for the NLC and for TESLA, it emerges that a compromise between peak luminosity and precision will be a likely outcome. This arises due to the severe requirements on the uncertainty in the luminosity weighted collision energy (Ecm). We consider the cases with and without a polarized positron beam. 
P.C. Rowson and M. Woods