The paper considers a private ownership economy in which economic agents could realize their aims at given prices, Walras Law is satisfied but agents’ optimal plans of action do not lead to an equilibrium in the economy. It means that the market clearing condition is not satisfied for agents’ optimal plans of action. In this context, the paper puts forward three specific adjustment processes resulting in equilibrium in a transformation of the initial economy. Specifically, it is shown, by the use of strict mathematical reasoning, that if there is no equilibrium in a private ownership economy at given prices, then, under some natural economic assumptions, after a mild evolution of the production sector, equilibrium at unchanged prices can be achieved.