The Tenth Amendment to the U.S. Constitution delegates powers outside of the limits of the federal government to state governments or to individual citizens. This amendment is notorious for expressing the reserved powers within the U.S. Constitution.
Powers within the purview of the national government include certain aspects of taxation, federal regulation and interstate commerce. States have police powers along with certain tax and regulatory powers within an individual state. The reach of federalism within the amendment is subjective. The omission of specific powers to delegate to the states is the basis of many U.S. Supreme Court cases that decide the limits of both federal and state governments on an individual basis.