- 2015/07/08 - 2015/07/10 The 9-th International Conference on Complex, Intelligent, and Software Intensive Systems (CISIS-2015) Honorary Co-Chair
- 2015/07/08 - 2015/07/10 The Ninth International Conference on Innovative Mobile and Internet Services in Ubiquitous Computing (IMIS-2015) Honorary co-chair
- 2010/09 - NBiS2010, Takayama, Gifu, Japan, General co-chair
- 2010/06 - IEEE ICDCS2010, Genoa, Italy, International Liaison Co-chair
- 2010/02 - AReS2010, General co-chair, Krakow, Porland.
- 2009/09 - ICPP General Co-chair, Vienna, Austria.
- 2009/08 - NBiS2009 General co-chair, Indianapolis, USA.
- 2009/03 - AReS General co-chair, Fukuoka.
- 2006/01/01 - 2008/12/31 IEEE Computer Society Board of Governors
- 2006/01 - 2008/12 IEEE Computer Society Board of Governors (BOG).
- 2006 - 2008 情報処理学会 論文誌シニア査読者
- 2007/04/01 - 情報処理学会 論文誌シニア査読委員
- 2007/03 - AReS General co-chair, Barcelona, Spain.
- 2005 - 2007 IEEE Computer Society Board of Govenors (BOG) Board of Govenors (BOG)
- 2006/03 - AReS General co-chair, Vienna, Austria.
- 2004/01/01 - 2005/12/31 IEEE Computer Society, Audit Committee Member
- 2003/01/01 - 2005/12/31 IEEE Computer Society Board of Governors
- 2003/01 - 2005/12 IEEE Computer Society Board of Governors (BOG).
- 2005/04 - AReS General co-chair, Vienna, Austria.
- 2003 - 2005 IEEE Computer Soceity BoG (Board of Governors)
- 2003 - 2005 IEEE Computer Society TCDP(Technical Committee on Distributed Processing) Advisory Committee
- 2004/07 - IEEE IEEE ICPADS2004 General Co-chair, Fukuoka
- 2004/07 - IEEE IEEE ICPADS2004 General Co-chair, Fukuoka
- 2004 - IEEE Member of the Advisory Committee of the IEEE Computer Society Distinguished Visitors Programme (Asia/Pacific).
- 2004 - IEEE Member of the Advisory Committee of the IEEE Computer Society Distinguished Visitors Programme (Asia/Pacific).
- 2004 - IEEE Computer Society Senior member
- 2003/03 - IEEE IEEE ISORC2003 General chair, Hakodate
- 2003/03 - IEEE IEEE ISORC2003 General chair, Hakodate
- 2003/03 - IEEE IEEE AINA2003 General co-chair, X'ian, China
- 2003/03 - IEEE IEEE AINA2003 General co-chair, X'ian, China
- 2003/01/01 - IEEE Computer Society, Golden Core Member
- 2003 - IEEE IEEE AINA (International Conference on Advanced Information Networking and Applications URL:http://www.aina-conference.org/) Steering Committee Chair
- 2003 - IEEE IEEE AINA (International Conference on Advanced Information Networking and Applications URL:http://www.aina-conference.org/) Steering Committee Chair
- 2002/07/02 - 2002/07/05 IEEE IEEE Computer Society, General co-chair, International conference on distributed computing systems (ICDCS-1998), Vienna, Austria
- 2002/06 - IEEE IEEE ICDCS2002 General Co-chair, Vienna, Austria
- 2002/06 - IEEE IEEE ICDCS2002 General Co-chair, Vienna, Austria
- 2002/01/01 - IEEE Executive Committee Member of Technical Committee of Distributed Processing (TCDP)
- 2002 - IEEE Computer Society Executive Committee Member of Technical Committee of Distributed Processing (TCDP).
- 2002 - IEEE IEEE ICDCS Steering Committee Member
- 2002 - IEEE IEEE ICDCS Steering Committee Member
- 2002 - IEEE Computer Society Golden Core Member
- 1999/05/01 - 2001/04/30 情報処理学会 理事
- 1999/05/01 - 2001/04/30 Information Processing Society of Japan (IPSJ) Executive committee member
- 1999/05 - 2001/04 情報処理学会 理事.
- 1999/05 - 2001/04 IPSJ Board member
- 1997/04 - 2001/03 情報処理学会 マルチメディア通信と分散処理(DPS)研究会主査.
- 1997/04 - 2001/03 情報処理学会 Chair of IPSJ SIGDPS
- 1999 - 2001 情報処理学会 理事
- 1999 - 2001 IPSJ Executive Committee Member
- 2001 - 情報処理学会 フェロー
- 1999/05/01 - 2000/04/30 情報処理学会 情報規格調査会役員会理事
- 1999/05 - 2000/04 情報規格調査会 役員会理事.
- 1996/04/01 - 2000/03/31 情報処理学会 マルチメディア通信と分散処理(DPS)研究会主査
- 1996/04/01 - 2000/03/31 Information Processing Society of Japan (IPSJ) Chair of SIGDPS
- 2000 - IEEE IEEE ICPADS2000, Program chair, Iwate
- 1997 - 1999 情報処理学会 マルチメディア通信と分散処理研究会主査
- 1997 - 1999 IPSJ(Information Prosessing Society of Japan) Chair of SIGDPS
- 1998/06 - IEEE ICDCS(International Conf. on Distributed Computing Systems) 1998 Program co-chair, Amsterdam, The Netherland.
- 1998/05/26 - 1998/05/29 IEEE IEEE Computer Society, Program co-chair, International conference on distributed computing systems (ICDCS-1998), Amsterdam, The Netherland
- 1998 - NBiS (International Con. on Network-based Information Systems http://www.takilab.org/conf/nbis) Steering Committee Chair (1998- NBiS Chair).
- 1996/05/01 - 1997/04/30 情報処理学会 論文誌Aグループ主査
- 1995/04/01 - 1997/03/31 情報処理学会 調査研究運営委員会委員
- 1996/04 - 1997/03 情報処理学会 論文誌Aグループ主査.
- 1996 - 情報処理学会 論文誌編集委員会Aグループ主査
- 1990/04/01 - 1994/03/31 情報処理学会 マルチメディア通信と分散処理(DPS)研究会幹事
- 1990/04 - 1994/03 情報処理学会 マルチメディア通信と分散処理(DPS)研究会幹事.
- 1992 - 1994 情報処理学会 マルチメディア通信と分散処理研究会幹事
- 1986/01/01 - IEEE IEEE Computer Society, Steering committee co-chiar and founder, International Conference on Advanced Information Networks and applications (AINA)