GPD program at COMPASS

The study of exclusive reactions like Deeply Virtual Compton Scattering (DVCS) and Meson Production is one major part of the future COMPASS program1 in order to investigate nucleon structure through Generalised Parton Distributions (GPD). The high energy of the muon beam allows to measure the $x_{B}$-dependence of the $t$-slope of the pure DVCS cross section and to study nucleon tomography. The use of positive and negative polarised muon beams allows to determine the Beam Charge and Spin Difference of the DVCS cross sections to access the real part of the Compton form factor related to the dominant GPD H.