The analytical categories elaborated by Wesley Newcomb Hohfeld provide substantial insights into American constitutional law, in particular the Ninth Amendment. The Constitution mainly governs the powers of government and the limits thereon, and four of Hohfeld’s eight fundamental legal conceptions deal specifically with power and its absence. In terms of Hohfeld’s concepts, the government may have power or be subject to disability, and private people may correlatively be liable to or immune from government power. By distinguishing between rules concerning power and rules concerning other legal relations like duties and claim-rights, Hohfeld’s concepts clarify an especially important function of constitutional rules: to protect from government power legal interests that are not themselves produced by the Constitution. The Takings Clause of the Fifth Amendment operates this way when it limits the federal power of eminent domain with respect to property interests created by state law; property owners enjoy Hohfeldian claim-rights, for example, that are distinct from immunity from federal power. Constitutional discourse also provides many confirmations of Hohfeld’s observation that the word “right” has multiple and potentially confusing uses. Hohfeldian analysis, and that observation about the terminology of rights, support the argument that the Ninth Amendment reinforces the principle of enumerated federal power by barring the inference that the federal government has every power that is not denied to it by an affirmative limitation. The interrelations among Hohfeld’s categories shows how a grant of power to government is intrinsically a reduction of the immunity of private people from government power, because it subjects some of their legal interests to that power. For the people to grant a power is thus in a sense to surrender the legal interests that are subject to the power. When no power is granted, legal interests not subject to power are retained. Legal interests not created by the Constitution but protected by the principle of enumerated federal power thus come within the concept of the other rights retained by the people referred to by the Ninth Amendment. Because the Constitution itself assumes the existence of legal interests that are protected by but do not derive from it, any assumption by the Ninth Amendment that the people retain rights is satisfied by the existence of legal interests that are beyond federal power because of limited enumeration. While the concept of other rights retained by the people includes natural rights, if there are any, the Ninth Amendment is neutral as to whether they exist and if so what their consequences are.