Operation and Performance of the CMS Silicon Tracker

The CMS silicon tracker is the largest silicon detector ever built. It consists of a hybrid pixel detector with 66 million channels and a 200~m$^2$ silicon strip detector with 10 million readout channels. We describe the operation of this detector during the first three year of LHC both during proton-proton as well as heavy ion collisions with results on the operational performance, calibration, signal-to-noise ratio, timing, etc. The resolution and efficiency of the track and vertex reconstruction are measured with data and compared to results from simulation. With increasing integrated luminosity, monitoring of radiation-induced effects becomes more and more important. Our methods for measuring the evolution of full depletion voltage and leakage current will be presented and the results discussed.