The Multi-Unit Spectroscopic Explorer (MUSE) is an integral-field spectrograph for the VLT for the next decade. Using an innovative field-splitting and slicing design, combined with an assembly of 24 spectrographs, MUSE will provide some 90, 000 spectra in one exposure, which cover a simultaneous spectral range from 465 to 930nm. The design and manufacture of the Calibration Unit, the alignment tests of the Spectrograph and Detector sub-systems, and the development of the Data Reduction Software for MUSE are work-packages under the responsibility of the AIP, who is a partner in a European-wide consortium of 6 institutes and ESO, that is led by the Centre de Recherche Astronomique de Lyon. MUSE will be operated and therefore has to be calibrated in a variety of modes, which include seeing-limited and AO-assisted operations, providing a wide and narrow-field-of-view. MUSE aims to obtain unprecedented ultra-deep 3Dspectroscopic exposures, involving integration times of the order of 80 hours at the VLT. To achieve the corresponding science goals, instrumental stability, accurate calibration and adequate data reduction tools are needed. The paper describes the status at PDR of the AIP related work-packages, in particular with respect to the spatial, spectral, image quality, and geometrical calibration and related data reduction aspects.