This paper considers Stackelberg competition in a general equilibrium framework with production. The working of market power and the confi...gurations of strategic interactions are complexi...ed by the presence of an active leader. Two market price mechanisms are here studied: one is associated with the Stackelberg-Walras equilibrium, the other is linked to the Stackelberg-Cournot equilibrium. In the context of an exchange economy with a production sector, several results are obtained about equilibria mergings and about welfare comparisons.