m2 of double-sided silicon strip detectors and more than 1 m2 of silicon drift detectors, it is the largest system using both types of silicon detector. ALICE has recently presented plans for an upgraded Inner Tracking System, mainly based on building a new silicon tracker with greatly improved features in terms of determination of the impact parameter (d0) to the primary vertex, tracking efficiency at low pT and readout rate capabilities. The upgraded ITS will open new channels in the study of the Quark Gluon Plasma formed at LHC which are necessary in order to understand the dynamics of this condensed phase of the QCD. It will allow the study of the process of thermalization of heavy quarks in the medium by measuring heavy flavour charmed and beauty baryons and extending these measurements down to very low pT for the first time. It will also give a better understanding of the quark mass dependence of in-medium energy loss and offer a unique capability of measuring the beauty quarks while also improving the beauty decay vertex reconstruction. Finally, the upgraded ITS will give us the chance to characterize the thermal radiation coming from the QGP and the in-medium modification of hadronic spectral functions as related to chiral symmetry restoration. The upgrade project requires an extensive R&D effort by our researchers and collaborators all over the world on cutting-edge technologies: silicon sensors, low-power electronics, interconnection and packaging technologies, ultra-light mechanical structures and cooling units. Time Projection Chamber The ALICE Time Projection Chamber (TPC) is a large volume filled with a gas as detection medium and is the main particle tracking device in ALICE. Charged particles crossing the gas of the TPC ionize the gas atoms along their path, liberating electrons that drift towards the end plates of the detector. The characteristics of the ionization process caused by fast charged particles passing through a medium can be used for particle identification. The velocity dependence of the ionization strength is connected to the well-known Bethe-Bloch formula, which describes the average energy loss of charged particles through inelastic Coulomb collisions with the atomic electrons of the medium. Multiwire proportional counters or solid-state counters are often used as detection medium, because they provide signals with pulse heights proportional to the ionization strength. An avalanche effect in the vicinity of the anode wires strung in the readout chambers, gives the necessary signal amplification. The positive ions created