Owners of stochastic assets can pool their endowments to smoothen and insure individual payoffs across outcomes and time. We explore, in such a setting, how contingent shadow prices on aggregate resources can be used for three purposes: First, to design mutual contracts for risk averse agents; second, to quantify the malfunctioning of such contracts when there are risk lovers (or scale economies); and third, to estimate reasonable premiums for insurance offered by outside agents.