* Acting Chairman, Instituto de Matemática, Universidade de

Brasília, Brasília, 1967.

* Dean of Arts and Sciences (Coordenador Geral dos

Institutos), Universidade de Brasília, Brasília, 1968.

* Founding Member and Secretary General of the Sociedade

Brasileira de Matemática, Rio de Janeiro, 1967-1970.

* Member of the Board of Directors, Canadian Mathematical

Society, 1975-1979.

* Vice-president, Canadian Mathematical Society, 1977-1979.

* Member of the Publication Committee,Canadian Mathematical

Society, 1977-1979.

* Editor-in-chief (with E.G.Goodaire), Canadian Mathematical

Bulletin, 1980-1983.

* President, Canadian Mathematical Society, 1983-1985.

* Member of the Executive, Canadian Mathematical

Society, 1985-1987.

* Member, Grant Selection Committee for Scientific

Publications, NSERC Canada, 1986-1989.

* Coordinatore Collegio dei Docenti, Dottorato Ricerca in

Matematica, Consorzio Brescia - Milano - Pavia - Politecnico

Milano, 1992 to 1995.

* Coordinatore nazionale gruppo 40% MURST (Topologia),

1995 to 1998.

* Member, Board of Directors, Unione Matematica Italiana (Bologna),

1994-1997 and 1997-2000.

* Member, Board of Directors, Scuola Matematica

Interuniversitaria (Firenze), 1995-2000.

* Executive Vice-President, Istituto Nazionale di Alta

Matematica, Roma, 1995 to 1999.

* Member, Editorial Board, Rendiconti di Matematica (Roma),

1995-1999.

* Council member of the European Mathematical Society, 1995-

1998.

* Director, Scuola per le Applicazioni della Matematica

nell’Industria (SAMI), Milano, 1998-2002.

* Member of the Executive Committee, European Mathematical

Society, from Jan. 1, 1999.

* Canadian Mathematical Society (life member).

* American Mathematical Society (since 1962).

* Unione Matematica Italiana.

* European Mathematical Society.

* Societé Mathématique de France.