An interdisciplinary program committee (PC) discusses the scientific orientation of the SPP's research program in general as well as planned priorities and additional activities. In addition, the PC decides on the use of the SPP's central funds. The Program Committee is established at the kick-off meeting. It includes the coordinator, the postdoc and the five cluster representatives. The PC meets for regular control meetings during the annual meetings of the SPP. In the intervening periods, special meetings may be held via video conference, if necessary, upon the initiative of the coordinator.