Number Theory Centres:Listed in the Number Theory Web.
(Austria) Technical University of Graz: Algorithmic and Probabilistic Number Theory Research Group. Members, research interests.
(Austria) University of Natural Resources, Vienna: Number theory group led by Werner Georg Nowak. Members, research interests, publications, links.
(Austria) University of Vienna: Johannes Schoißengeier's number theory research group. Members, research interests, links to other Austrian number theorists.
(Canada) CICMA, Concordia University, Montreal: Number Theory Page. Members, seminars, preprints.
(Canada) McMaster University: Algebra/Number Theory Seminar. Meetings, abstracts.
(Canada) Queen's University, Kingston: Algebra and Number Theory Group. Members, research interests.
(Canada) University of British Columbia: Number Theory group. Members, research areas and meetings.
(Canada) University of Toronto: Number Theory/Representation Theory Seminar. Schedule of meetings.
(China) Shandong University: Number theory research group. Members, research interests, courses, events.
(Croatia) University of Zagreb: Seminar on Number Theory and Algebra. Members, seminars, links.
(Europe) Arithmetic Algebraic Geometry: A European network of 12 working groups from 6 countries.
(Europe) GTEM: Galois Theory and Explicit Methods in Arithmetic: Research training network coordinated in Paris, uniting twelve teams from July 2000 until June 2004.
(Finland) University of Turku: Number Theory Group. Members, research interests.
(Germany) Clausthal University of Technology: Institut für Mathematik - Number Theory Research Group. People, research topics.
(Germany) Technische Universität, Berlin: Algebra and Number Theory: the KANT group. Members, software (KANT/KASH), publications.
(Germany) University of Heidelberg: Algorithmic Algebra and Number Theory. Members, research, activities, software, links.
(Germany) University of Regensburg/Leipzig: Algebraic Cycles and L-Functions research group. People, preprints, seminars, workshops, positions, news.
(Germany) University of Siegen: Algebra and Number Theory group. Members, research interests.
(Hungary) Alfréd Rényi Institute of Mathematics, Hungarian Academy of Sciences: Number Theory research group staff.
(Hungary) Eötvös University, Budapest: Department of Algebra and Number Theory. Members pages.
(Hungary) Lajos Kossuth University, Debrecen: Department of Algebra and Number Theory. Staff list.
(Israel) Ben Gurion University of the Negev: Number Theory and Algebraic Geometry Research Group. Members, research interest, seminars.
(Italy) University of Pisa: Number Theory Group. Research interests and members.
(Japan) Okayama University: Number Theory Group. Members.
(Lithuania) Vilnius University: Department of Probability Theory and Number Theory.
(Netherlands) CWI, Amsterdam: Computational number theory group. Members, research interests, publications.
(Netherlands) University of Leiden: Number theory research group. Staff, events, links.
(Poland) Polish Academy of Sciences: Department of Number Theory. Members, research interests, publications.
(Russia) Steklov Institute, Moscow: Department of Number Theory. History, research projects, profiles.
(Russia) Steklov Institute, St. Petersburg: Laboratory of Number Theory. Research interests.
(Singapore) National University: Algebra and Number Theory Seminar. Schedule of meetings.
(Slovakia) Comenius University, Bratislava: Department of Algebra and Number Theory. Research topics, contact information.
(South Africa) The John Knopfmacher Centre for Applicable Analysis and Number Theory, University of the Witwatersrand: Members, research interests, preprints, meetings.
(Spain) Seminari de Teoria de Nombres de Barcelona (UPC): Members, research topics, publications, schedules.
(Sweden) Uppsala University: Mathematics III research group: quantum chaos and number theory.
(UK) Cardiff University: Number Theory Group. Members, research interests, advice to research students.
(UK) King's College, University of London: Number Theory Group. Staff, meetings, preprints.
(UK) Nottingham University: Number Theory and Arithmetic Geometry research group. Research interests, members, visitors, meetings.
(UK) Royal Holloway, University of London: Research areas (mainly analytic/combinatorial), members.
(UK) University of Bristol: Number Theory group. Staff, students, events, links.
(UK) University of Cambridge: Number Theory Seminar. Meetings.
(UK) University of Durham: Geometry and Arithmetic Group. Members, meetings, preprints.
(UK) University of East Anglia: Number Theory research.
(UK) University of Glasgow: Number Theory and Combinatorics. Staff, research interests.
(UK) University of Oxford: Number Theory Group. Members, publications, meetings.
(UK) University of York: Number Theory Research Group.
(Ukraine) Tavrical National University: Department of Algebra and Number Theory. Members, research interests, publications.
(USA) Boston University: Algebra and Number Theory Research Group. Members, research interests, seminars, courses.
(USA) Brown University: Number Theory/Arithmetic Geometry Seminar. Members, meetings.
(USA) Caltech: Underground Number Theory Seminar. Schedule of meetings.
(USA) New York Joint Number Theory Seminar: Rotates between Columbia University, CUNY Graduate Center and NYU.
(USA) Penn State: Algebra and number theory group. Members, seminars, preprints, links.
(USA) Southwestern Center for Arithmetical Algebraic Geometry: Based at the University of Arizona, in collaboration with the Universities of New Mexico, Southern California, and Texas. Annual conference.
(USA) Texas A and M University: Combinatorics/Number Theory Directory.
(USA) University of California Irvine: Number theory seminar. Meetings, study groups, links.
(USA) University of California, Los Angeles: Number Theory Group. Members, events, resources.
(USA) University of California, Santa Barbara: Arithmetic and Geometry Seminar. Meetings.
(USA) University of California, Santa Cruz: Number Theory Seminar meetings.
(USA) University of Georgia: Number Theory and Arithmetic Geometry Group. Members, seminars.
(USA) University of Illinois at Urbana-Champaign: Number Theory faculty, visitors, meetings, courses, events.
(USA) University of Rochester: Algebra and Number Theory Group. Members, research interests, seminar schedule.
(USA) University of South Carolina: Number Theory Group. Members, research interests, courses, links.
(USA) University of Texas: Number Theory Group. Members, meetings, software.
(USA) University of Wisconsin, Madison: Algebra, Combinatorics and Number Theory Group. Members, seminars.
(USA)University of Michigan: Graduate Program in Number Theory. Staff, research interests, courses, seminars.