Although social scientists have sought to understand riots in terms of social structure, few causal explanations have withstood the tests of ongoing empirical examination. In America, presidential commissions sought to put the black urban riots of the mid-sixties in a similar context. Despite the laudable attempts at deriving benign policy implications from such explanations, the commissions’ explanations were no better than the social science of the time. Understanding the causal basis of riots has been elusive, but our understanding of riots as problems of crisis management has been far more reachable. A comparison of two Los Angeles riots, Watts 1965, and the Rodney King riots of 1992, shows that the intensity, spread and duration of the riots were a function of crisis paralysis. We might not know, in any scientific sense, what causes riots but we appear to know a great deal about the consequences of not appropriately preparing for or managing riots. These are the lessons of both Los Angeles riots.