The CMS tracker-Construction issues for large detector systems with industry involvement

445 m2 of wafer material will be used to cover the active tracking volume with 24,328 silicon sensors with a surface of 206 m2. 75,376 APV front-end chips with 9,648,128 electronic channels will be available on 11,920 modules (partially double sided). This unprecedented detector requires attention to logistics, industry involvement, quality assurance issues and design validations. These will be discussed in this document.