In principle, foreigners wishing to enter Japan (with the exception of ship and airline crews) are required to apply at an overseas Japanese diplomatic establishment (embassy or consulate) for a visa to be stamped in or attached to their passport valid for travel to Japan.
Nationals of some countries and regions holding valid passports, however, can apply for landing permission for short-term stays for such purposes as sightseeing and business trips without obtaining a visa.
Please see the following webpage for the "list of countries and regions that have visa exemption arrangements with Japan."
http://www.mofa.go.jp/j_info/visit/visa/short/novisa.html
If you are not sure whether you need a visa to enter Japan or not, please contact the diplomatic mission (embassy or consulate) in your country or in your living area.
http://www.mofa.go.jp/about/emb_cons/over/index.html
In case you need an entry visa to Japan, you will be required to submit two documents, both written in Japanese:
a.. an invitation letter by the conference (APMC 2010)
b.. a detailed schedule during your stay in Japan
All the speakers, session chairs, committee members of APMC 2010, and their acquaintances or family members can obtain these documents from the APMC 2010 Steering Committee under the condition that they...
a.. complete the Pre-Registration with all payments done
b.. have all the travel arrangements finished, such as hotel accommodations and airline tickets