Performance requirements for the Phase-2 Tracker Upgrades for ATLAS and CMS

The High-Luminosity operation of the LHC poses unprecedented challenges for the design of the Upgraded Trackers of ATLAS and CMS. The stringent requirements imposed by the high particle density and integrated fluency reduce the phase-space of valid technical solutions, inducing both Collaborations to design all-silicon trackers. On the other hand constraints and requirements coming for the rest of the detector lead to some different choices, especially for the Outer Trackers.The main requirements for the two Tracking systems are reviewed, discussing the implications for the detector designs and layout, and explaining why some of the technical choices remain different in the two experiments. To conclude, some expected performance figures for the two tracking systems are presented.