Lucky for me!

Yes and no. My new name will be Vivian Lee Yamada but on paper (legal documents, forms of identificaiton, etc.) it will remain Vivian Lee due to various complications and considerations.

In Japan, the civil law forces a common surname for every married couple, unless in a case of international marriage. In most cases, women surrender their surnames upon marriage, and use the surnames of their husbands. (that is, unless the woman is heir to a company, large fortune, or other such ties...in which case the husband marries into the family while adopting her surname)

As for women who want to keep their maiden name, people are figuring out ways around the bureaucracy. One ploy is the "paper divorce/remarriage." Others are opting for a "de factomarriage," which means that while they might very well have a religious ceremony, they don't legally register their marriage, so husband and wife can keep their surnames. This is particularly beneficial for women (in Tsukuba) with an advancing career and many academic papers under her maiden name.