AbstractGiven a set ofnjobs to be processed on a single machine, the problem is to find an optimal job sequence that hierarchically minimizes a bi-criterion objective function. The primary criterion is the maximum value of a general non-decreasing penalty function of job completion time, while the secondary criterion is total job flow time. An extension of Emmons's result is presented on the basis of which an improved solution procedue is developed to reduce the computational effort to find the optimal solution.