The CMS Pixel Detector for the High Luminosity LHC

The LHC machine will be upgraded to increase its peak luminosity to $5\mbox{--}7.5\times10^{34}$ cm$^{-2}$s$^{-1}$ and to possibly reach an integrated luminosity of $3000\mbox{--}4000\;$fb$^{-1}$, with an average number of pileup events of $140\mbox{--}200$. The CMS experiment needs to be upgraded to keep up with the new challenges: the unprecedented radiation environment translates to the detector requirement of high resilience, while the increased number of events per bunch crossing requires higher detector granularity. Thus a completely new Inner Tracker will be installed. Design choices for the Inner Tracker Phase-2 upgrade, highlighting R\&D activities and technological approaches, will be presented.