The Japanese imperial dynasty, the longest reigning family in the world today, faces the danger of extinction. If this happens then Crown Prince Naruhito will become the last emperor of Japan and the last one in the world. In the past, the dynasty, whose very legitimacy rested on its long and unbroken existence, developed various institutions to insure its survival. These included concubinage and back-up collateral families. The democratic reforms, which abolished these institutions, and the present lack of young male descendants, endanger the continuity of the imperial family. Several solutions have been suggested, but all of them are problematic. The great question is whether the Japanese people will continue to support the institution and to what extent they will be ready to change its long-existing succession rules.