Potential and challenges of the CMS barrel muon system

In a hadronic environment, distinct decay kinematics are essential to efficiently trigger on the interesting physics events. The CMS experiment will exploit a system of four muon tracking stations based on 200,000 drift tubes to identify muons and to measure their charge and momentum. The physics requirements are discussed and it is shown how they are fulfilled in terms of design and quality control during production. The chambers are tested with cosmic muons and test beams.