In this research work, development of a multi-response optimization technique has been undertaken, using traditional desirability analysis and non-traditional particle swarm optimization techniques (for different customer’s priorities) in wire electrical discharge machining (WEDM). Monel 400 has been selected as work material for experimentation. The effect of key process parameters such pulse on time (TON), pulse off time (TOFF), a peak current (IP), wire feed (WF), were investigated on material removal rate (MRR) and surface roughness in WEDM operation. Further, the responses such as MRR and SR were modeled empirically through regression analysis. The developed models can be used by the machinists to predict the MRR and SR over a wide range of input parameters. The optimization of multiple responses has been done for satisfying the priorities of multiple users by using Taguchi-desirability function method and particle swarm optimization technique. The analysis of variance (ANOVA) is also applied to investigate the effect of influential parameters. Finally, the confirmation experiments were conducted for the optimal set of machining parameters, and the betterment has been proved. © 2016, Pharmainfo Publications. All rights reserved.