This chapter offers a conceptual analysis of toleration in order to give a clear definition of the central liberal tenet. It isolates toleration from other notions; this provides people some guidance by introducing seven definitional conditions of toleration. Toleration has been called "the substantive heart of liberalism". Toleration is not indifference or simple noninterference. Liberalism requires a normative principle of toleration to adjudicate interference. In order to have a principle of toleration, one must be clear about what toleration is. Toleration is not pluralism, the view that insists there are multiple genuine values. Importantly, the claim that there is cultural diversity is distinct from pluralism, understood as the view that there are plural values. The advocate of multiculturalism, that is, promotes multiple cultures. Those advocating for the value of multiple cultures may wish to make toleration more intertwined with their view.