The US Constitution never mentions “city,” “county,” or “township,” not even “local” or “municipal” governments. It concerns itself only with sovereign entities. Because local governments “cannot claim to be sovereigns” and because whatever power a local government has tends to flow from its state, that sounds like the end of the matter. But local governments still exercise sovereign powers, including law enforcement, eminent domain, education, taxing, zoning, and other indispensable “attributes of sovereignty.” Even if the US Constitution does not mention cities by name and even if cities cannot claim sovereign status, the federal charter still has ample consequences for municipal governments. This chapter takes vertical separation of powers one step further, to federalism within federalism. It explains the division of powers between state and local governments and chronicles disputes that have arisen between them. If, in modern America, like-minded people increasingly gravitate to similar states, the same is true within states, whether in cities, suburbs, or rural areas. Home rule and other local allocations of power sometimes allow people in these communities to express their distinct political preferences and live under them, too.