After 1989, he has served as leader of the Project on Building a Co–operative Security System in and for Europe at the Stockholm International Peace Research Institute (SIPRI). He was appointed as Director of SIPRI from 1 July 1991 and re–elected in 1996 for a second term, lasting until June 2002. He is a member of many consultative bodies and scientific councils, including the Institute of Political Studies at the Polish Academy of Sciences. He is co-chairman of Polish-Russian Group on Difficult Matters.