世界の債務は、世界金融危機及びコロナ危機を経て、政府債務、企業債務が著しく拡大し、過去最大の水準に達した。債務が将来における返済を前提とした購買力の一時的移転であることを考えると、債務により賄われる支出の成長促進効果が重要である。他方、過去の債務不履行事例における債務水準のばらつきの大きさや高インフレによる債務の価値の棄損や市場アクセスの喪失など債務がもたらす困難の広範性を考えると、高債務がもたらしうる問題を回避するためには、債務の持続可能性を債務 /GDP比などの債務指標で見ていくだけでは十分でなく、当該国の過去の債務不履行、高インフレなどの履歴、国内成長率、米国金利、為替レートなど関連性のある幅広い内的・外的要因を慎重にモニターしていくことが不可欠であると思われる。The global debt has reached the historically highest level due to significant expansion of debt owed by the government and private non-financial corporations after the Global Financial Crisis and the Corona Crisis. Considering the fact that debt is a temporary transfer of purchasing power under the commitment to repay it in the future, it is important that the fund obtained by debt is used in a growth enhancing manner. At the same time, in light of the significant dispersion of the debt levels in the past default cases and the extensiveness of difficulties that debt accumulation may bring about, such as the reduction of real value of debt due to high inflation and loss of market access, it seems insufficient to solely watch debt sustainability by checking debt related indicators such as debt/GDP ratio. In order to avoid problems that may be caused by high debt, it is crucial to carefully monitor wide ranging domestic and external factors including the historical record of the country in question relating to such incidents as the past default and high inflation, domestic growth rate, US interest rate, foreign exchange rate and other indicators that seem to be relevant.