Limits on the Accuracy of Drift Chambers and Calibration Beams

years from now. The understanding of intrinsic limits on the spatial accuracy of drift chambers, and the development of new methods for calibrating them, are therefore still relevant. The present talk attempts to review the state of the art. In order to see what are the main questions to be asked, I have summarized in Table 1 the main characteristics of the drift-chamber detectors proposed for LEP. These detectors fall into two classes: i)