Although the logical empiricism movement and its program took root in a number of European cities (including Prague and Warsaw), it seems undoubted today, however, that "the projects characteristic of logical empiricism developed primarily in Vienna and Berlin" as Alan Richardson and Thomas Uebel put it only a few years ago. As for these two centres, however, it was Vienna that has attracted much more attention from the scientific community in history and philosophy of science (HPS) in recent decades. Systematic research on the Vienna Circle already started decades ago and has gotten well established today not only in its place of origin but also in many other European countries and above all in North America. In contrast, there have been until now only a few studies on the Berlin Group and its members.