In 2005 Japan introduced a new quarantine system for dogs, cats and other animals being imported into the country. Pets may have to go into quarantine for up to 180 days.

Dogs and cats being brought into Japan must be micro chipped and have proof of rabies vaccination within the previous 12 months. They must have a Fluorescent Antibody Viral Neutralization (FAVN) Test, to confirm they are protected against rabies, and a health and rabies certificate issued by a qualified veterinarian.

The Japan Animal Quarantine Service website provides detailed requirements for the import of dogs, cats and other animals into the country.

Added March 2007 by Chris:
The most recent laws for importing pets took effect as of June 1, 2006. [Importers from UK or Australia do not have to go through this process.] The microchipping and rabies vaccinations are still required. After the second vaccination, blood is drawn and sent to a Ministry of Agriculture approved location for processing. 180 days from their approval date, the animals can be imported and can expect a MAXIMUM of 12 hours in quarantine. Importing before the 180 limit will require quarantine of the remainder until 180 days is reached + 1 day for processing. The rules are on the Japan Ministry of Agriculture website.