A modification of the Routh approximant is introduced which results in a considerable improvement over the conventional Routh approximation technique. Since some amount of arbitrariness is available in the time moment expressions of the conventional Routh approximant, it can be utilized to minimize the step response error while preserving the stability and moment matching property of the conventional Routh approximant. A numerical example illustrates the procedure. Copyright © 1986 by The Institute of Electrical and Electronics Engineers, Inc.