Gaia, the forthcoming astrometric mission of ESA, will provide unprecedented positional and radial velocity measurements with the accuracies needed to produce a stereoscopic and kinematic census of about one billion stars in our Galaxy and throughout the Local Group. Gaia data of Extended Objects (galaxies, AGN host galaxies, planetary nebulae etc) require special treatment. The Gaia Division Unit Extended Objects (EO) of CU4 (Object Processing) develops the algorithms for the proper reduction of the corresponding observations. We present the status of progress of its Work Packages, achievements and remaining problems.