1996. Co-organizer for CNTA V.
1999. Main Organizer for the conference on The Mathematics of Public-Key Cryptography, Fields Institute, June 1999.
1999. Programme Committee member for CATS 2000 Australasian Conference on Discrete Mathematics and Theoretical Computer Science, Australian National University, Canberra, Australia, February, 2000
2000. Programme Committee member for a conference on Number Theory and Public Key Cryptography, Polish Academy of Sciences, Warsaw, Poland, September, 2000.
2000. Co-organizer for a Special Session on Number Theory and Cryptography, CMS Summer Meeting, McMaster University, June, 2000.
2002. Co-organizer for the 7th Conference of the Canadian Number Theory Association, Concordia University, Summer 2002.
2003. Main Organizer for a Conference in Number Theory in Honour of the 60th birthday of Professor H.C. Williams, The Banff Center, Banff, Alberta, Canada, May 24-30, 2003.
2008. Main Organizer for a Special Session in Number Theory at the 7th Australia-New Zealand Mathematics Convention, Christchurch, New Zealand, December 8-12, 2008.
2009. Co-organizer for a Conference in Number Theory, Carleton University, Ottawa, June 2009.
2010. Main Organizer for a BIRS workshop in honour of Cam Stewart, Banff, May 2010.