We show that when the government has a target debt level, mul-tiple equilibria exist because of a complementary relationship between the government and individuals. One is associated with a high fertility rate and a high pension level. The other is associated with a low fertility rate and a low pension level. Furthermore, a strict target level of government debt tends to reduce the low fertility rate. We obtain the same results with consumption taxes. The government should provide adequate security for individuals during their retirement years not to cause a failure of coordina-tion between the government and individuals.