In this study, we address a rescheduling problem in parallel machine environments under machine eligibility constraints. We consider total flow time as efficiency measure and the number of jobs processed on different machines in the initial and revised schedules as a stability measure. We present an optimizing algorithm for minimizing the stability measure subject to the constraint that the efficiency measure is at its minimum level. We then propose several heuristic procedures to generate a set of approximate efficient schedules relative to efficiency and stability measures. (C) 2002 Elsevier Science B.V. All rights reserved.