The present issue focuses on staircases, paths and ramps – in other words, building elements and spaces that in addition to their obvious technical functions often have to play a formal role. Circulation and access spaces have always attracted special attention in notable structures, as one sees from the magnificent staircases of Baroque palaces to the constructional gestures of modern high tech. For example, the House for Music and Music Theatre of the University for Art in Graz by Ben van Berkel (page 606) welcomes visitors with the dynamic spatial configuration of its foyer and other opulent visual attractions. In complex developments like airports or railway stations, however, clear spatial situations alone are not enough to control circulation, which is why sign systems are used as an aid to orientation. On page 564, Oliver Herwig explains the main requirements of such systems. On page 628, Oliver Heiss considers the word “threshold” in architecture, discussing how it may be overcome and cease to be a physical barrier. In their Arts and Cultural Centre in Paris (page 602), Jakob + MacFarlane use the requisite access routes to create a fascinating facade sculpture, as Piano and Rogers once did at the end of the 1970s in their staircase tubes on the Centre Pompidou.