In this paper the hydro-thermal scheduling problem is discussed. An interconnected hydro-thermal electric power system is scheduled such that maximum economy is achieved. The schedules obtained are designed to meet a specified active power demand and simultaneously to satisfy energy constraints imposed on the hydro-plants generations. The scheduling problem is solved by the use of functional analysis and, in this case, the minimum norm problem formulation is employed. It is emphasized that the optimal solution found here is guaranteed to be the unique optimal solution. The practical implementation of finding the generation schedule is illustrated by way of two examples.