However, sometimes incorrectly regarded as a degree, the Habilitation is a higher academic qualification in Germany, Austria and Switzerland that allows further teaching and research endorsement after a doctorate. It is earned by writing a second thesis (the "Habilitationsschrift") or presenting a portfolio of first-author publications in an advanced topic. The exact requirements for satisfying a Habilitation depend on individual universities. The "habil.", as it is abbreviated to represent that a habilitation has been awarded after the doctorate, was traditionally the conventional qualification for serving at least as a "Privatdozent" (e.g. "PD Dr. habil.") (senior lecturer) in an academic professorship. Some German universities no longer require the Habilitation, although preference may still be given to applicants who have this credential, for academic posts in the more traditional fields.