The spring meeting of the Arbeitskreis Festk¨orperphysik in the World Year of Physics 2005, the Einstein Year, was held from 4–11 March 2005 in Berlin, together with the yearly meetings of the other Arbeitskreise and Fachverb¨ande of the Deutsche Physikalische Gesellschaft. The total number of conference attendees was about 8000, mostly young physicists. The present volume of Advance…