The talk discusses the motivation for and challenges of obtaining magnetic information for ferromagnetic and antiferromagnetic systems on a length scale below 100nm. It reviews the principles of linear and circular x-ray magnetic dichroism spectro-microscopy and presents state-of-the-art results (20nm resolution) obtained with a dedicated soft x-ray photoelectron emission microscope (PEEM) installed on the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory. Results include studies of the antiferromagnetic domain structure at the surface of LaFeO3(100), NiO(100) and polycrystalline NiO and the ferromagnetic domain structure in hard/soft magnetic tunnel junctions. Future plans to reach a spatial resolution below 10nm will also be discussed.