Talks:

- Ganea's conjecture and the L-S category of a sphere-bundle over a sphere, Topology Seminar (Masaryk University, Brno, Cech Rep.), September 2003.
- On L-S category I and II, "Kinosaki Symposium on Homotopy Theory" (Kinosaki), January 2003.
- L-S category of Sp(n), Fukuoka Topology Symposium (Fukuoka U Seminar Hause, Fukuoka), December 2002.
- A p-complete version of Ganea's conjecture on co-H-spaces, Topology Friday Seminar (Kyushu U), November 2002.
- Lusternik-Schnirelmann category of Lie groups of low rank, Colloquium (Hannam U, South Korea), October 2002.
- Lusternik-Schnirelmann category of Lie groups of low rank, Colloquium (Taejon U, South Korea), October 2002.
- Recent progress on Lusternik-Schnirelmann category, Colloquium (Yonsei U, South Korea), October 2002.
- Lusternik-Schnirelmann category of a sphere-bundle over a sphere, Colloquium (Korea U, South Korea), October 2002.
- Ganea's conjecture on co-Hopf spaces, ICM'02 Satellite International Conference "Suzhou Satellite Conference on Algebraic Topology" (Suzhou U, P.~R.~China), August 2002.
- Recent progress on Lusternik-Schnirelmann category, ICM '02 Satellite International Conference Joint with Second Japan-Mexico International conference "Topology in Matsue" Plenary Talk (Shimane U), June 2002.
- L-S category of Sp(n), Topology Seminar (Fukuoka U), May 2002.
- A p-complete version of the Ganea conjecture for co-H-spaces, "Symposium on Homotopy Theory" (Osaka prefectural U), November 2001.
- Lusternik-Schnirelmann category of a sphere-bundle over a sphere, "Progress of rational homotopy theory and its application" (Ryukyu U), August 2001.
- Lusternik-Schnirelmann category of a sphere-bundle over a sphere, AMS-IMS-SIAM Joint Summer International Meeting "Lusternik-Schnirelmann Category in the New Millennium" Invited Talk (Mt. Holyoke College, USA), July 2001.
- Lusternik-Schnirelmann category of a sphere-bundle over a sphere, "International Conference in Algebraic Topology" (Isle of Skye, United Kingdom), June 2001.
- Lusternik-Schnirelmann category of a sphere-bundle over a sphere, Topology Friday Seminar (Kyushu U), June 2001.
- Lusternik-Schnirelmann category of a sphere-bundle over a sphere, "Workshop on Algebraic Topology" (Max-Planck-Institute-Bonn, Germany), March 2001.
- Unstable ring and homotopy set [SX,SX], "Homotopy Theory Symposium" (Ehime U), October 2000.
- Ganea's conjectures and their counter examples, "All Japan Topology Symposium" (Kagoshima U), July 2000.
- L-S category for some manifolds, Topology Seminar (Max-Planck Institute, Bonn, Germany), May 2000.
- Adjoint action of a finite loop space, Topology Seminar (University of Rochester), March 2000.
- Some problems by Ganea and their p-localised versions, "JAMI 2000" Invited Talk (Johns Hopkins University, USA), March 2000.
- A
_{∞}-method in L-S category, Topology Seminar (Johns Hopkins University, USA), March 2000. - Ganea's problems and (co)-projective spaces, "Meeting on Geometry and Phisics" (Shinshu U), November 1999.
- On some problems by Ganea, "Meeting on Homotopy Equivalences" (Il Palazzo Feltrinelli, Gargnano, Italy), September 1999.
- A
_{∞}-method in L-S category, Meeting of Mathematical Society of Japan (Topology Division) Special Talk (Gakushuin U), March 1999. - Kudo-Araki operations and torsion in 2-compact groups, Topology Friday Seminar (Kyushu U), December 1998.
- L-S category and the related topics, "Manifolds and Homotopy" (Kyushu U), December 1998.
- The Ganea conjecture on a co-H-space, ICM '98 Satellite International Conference "Algebraic Topology Meeting 1998 in Angers" Invited Talk (Angers University, France), August 1998.
- Ganea's conjecture on L-S category, Colloquium (Hiroshima U), May 1998.
- Ganea's conjecture on L-S category, Topology Seminar (Hiroshima U), May 1998.
- Adjoint action of a finite loop space II, Topology Seminar (Fukuoka U), May 1998.
- A
_{∞}-method in L-S category, Topology Friday Seminar (Kyushu U), April 1998. - The Ganea conjecture on a co-H-space, Topololgy Seminar (Fukuoka U), April 1998.
- The Ganea conjecture on a co-H-space, Kyoto Topology Seminar (Kyoto U), March 1998.
- A
_{∞}-method in L-S category - and the Ganea conjecture, "Manifold and Homotopy" (Kyushu U), January 1998. - Problems of Ganea on L-S category and a co-H-space, "Kinosaki Symposium on Homotopy Theory" (Kinosaki), January 1998.
- Ganea's conjecture on Lusternik-Schnirelmann category, Topology Seminar (Lille University, France), December 1997.
- Ganea's conjecture on Lusternik-Schnirelmann category, Topology Seminar (Aberdeen University, United Kingdom), November 1997.
- Ganea's conjecture on Lusternik-Schnirelmann category, Topology Seminar (Liverpool University, United Kingdom), October 1997.
- Ganea's conjecture on Lusternik-Schnirelmann category, Geometry Seminar (Edinburgh University, United Kingdom), October 1997.
- Adjoint action of a finite loop space, Topology Seminar (Aberdeen University, United Kingdom), April 1997.
- Adjoint action of a finite loop space, "Kinosaki Homotopy Theory Meeting" (Kinosaki), January 1997.
- Torsion in finite loop spaces, "Symposium on Transformation Groups" (Himeji), November 1996.
- An algebraic set representing A'
_{4}, "Symposium on Homotopy Theory" (Kochi U), November 1994. - The Ganea conjecture and quasi-projective modules, "Symposium on Transformation Groups and Homotopy Theory" (Nara Women's U), November 1992.
- On the Ganea conjecture, Colloquium (Hiroshima U), November 1992.
- Progress around Miller's theorem, "Geometric Homotopy Theory" (Okayama U), November 1991.
- Cohomology suspensions on finite Hopf spaces, "Symposium on Transformation Groups and Homotopy Theory" (Shinshu U), November 1991.
- Recent topics on H-spaces, Colloquium (Shinshu U), September 1991.
- The Pontryagin ring and torsion of H-spaces, "Okayama Topology Seminar" (Okayama U), May 1991.
- The Pontryagin ring and torsion of Lie groups, "Okayama Topology Seminar" (Okayama U), April 1991.
- Problems recently raised, "Homotopy Theory Meeting" (Tottori U), December 1990.
- Report on Adams Conference, "Symposium on Transformation Groups and Homotopy Theory" (Ehime U), October 1990.
- Generalized Whitehead Spaces with Few Cells, Topology Seminar (Oxford University, United Kingdom), August 1990.
- Homotopy associativity of sphere-extensions, "Symposium on Transformation Groups and Homotopy Theory" (Fukuoka U), January 1990.
- Generalized Whitehead Spaces with Few Cells, Topology Seminar (Aberdeen University, United Kingdom), August 1990.
- Generalized Whitehead spaces with few cells, "Topology Meeting" (Hiroshima U) December 1989.
- Generalized Whitehead spaces with few cells, "Meeting on Homotopy Theory" (Okayama U) September 1989.
- Homotopy associative Hopf spaces, "All Japan Topology Symposium" (Fukushima U) July 1989.
- H-spaces with generating subspaces and Homotopy associativity of sphere extensions, Colloquium (Kyushu U), October 1988.
- Homotopy associativity of sphere extensions and generating subspaces of Hopf spaces, Colloquium (Aberdeen University, United Kingdom), May 1988.
- Homotopy associativity of sphere extensions, Topology Seminar (Cambridge University, United Kingdom), April 1988.
- H-spaces with generating subspaces, Topology Seminar (Oxford University, United Kingdom), April 1988.
- H-spaces with generating subspaces, Topology Semianar (Liverpool University, United Kingdom), April 1988.
- Homotopy associativity of sphere extensions, Topology Seminar (Manchester University, United Kingdom), April 1988.
- H-spaces with generating subspaces, Geometry Seminar (Edinburgh University, United Kingdom), February 1988.
- Higher associativity of Hopf spaces, Topology Seminar (Aberdeen University, United Kingdom), October 1987.
- Miller conjecture and missing terms of an unstable Adams spectral sequence, Colloquium (Shinshu U), October 1986.
- A
_{n}spaces and A_{n}maps I & II, "Homotopy Theory and related topics" (Kyushu U), October 1986. - On the splitting of mapping spaces between classifying spaces, AMS-IMS-SIAM Joint Summer International Conference "Artin's Braid Group" (University of California, Santa Cruz, USA), July 1986.
- Maps from the classifying spaces, "Homotopy Theory of infinte-dimensional complex" (Osaka City University), January 1985.
- On A
_{n}structures on maps, "Study on unstable homotopy theory" (RIMS Kyoto U), July 1983. - On the ring structure of K
^{*}(XP^{n}), "Topology of H-spaces" (RIMS Kyoto U), February 1983.

Other activities:

- Organiser (with Ken-ichi Maruyama at Chiba U), "Self homotopy sets and related topics" (Chiba U), 16th - 18th December 2002.
- Organiser (with Toshio Sumi at Kyushu ID and Nobuyuki Oda at Fukuoka U), "Fukuoka Topology Meeting" (Fukuoka U Seminar House), 10th - 11th February 2001.
- Organiser (with Kouichi Hirata at Ehime U), "Symposium on Homotopy Theory" (Ehime U), 10th - 13th October 2000.
- Chair (at afternoon session 14th) "Algebraic Topology Meeting at Bellatera 2000" (Universit\'e Autonoma, Barcelona, Spain), 11th - 15th July 2000.
- Organiser (with Nobuyuki Oda at Fukuoka U), "Homotopy Theory Meeting" (Fukuoka U Seminar House), 18th January 2000.
- Organiser (Juno Mukai at Shinshu U, Igyou Kachi at Shinshu and Dai Tamaki at Shinshu), "Symposium on Homotopy Theory" (Shinshu U), 25th -28th October 1999.
- Organiser (with Akira Koyama at Osaka UE), "Geometric Homotopy Theory" (Okayam U), 17th - 18th November 1991.