Federalism and constitutionalism work together to limit and divide power through rules and institutions. Constitutionalism is crucial for federalism to function effectively, protecting multiple interests by spreading decision-making across different levels of government. This system ensures democracy by upholding principles like the rule of law, human rights, and the separation of powers. Without constitutionalism, federalism cannot properly organize pluralism. The relationship between federalism and constitutionalism is essential for maintaining a democratic society.