Wire Electrical Discharge Machining (WEDM) is an electrothermal non-traditional machining process used for machining electrically conductive materials that are difficult to machine. Material removal in WEDM is by means of spark erosion. WEDM is proven to be the alternative for producing complex parts with higher degree of dimensional accuracy and better surface finish. Over the years, a significant amount of research was globally carried out to explore the WEDM process capability. This paper aims to explore the research work carried on parametric influence of WEDM process variables on various output performance measures. The paper also highlights various modelling techniques to predict optimal machining conditions and explore the feasibility of applying WEDM process to machine advanced materials. Combined technology that benefits from the virtues of WEDM and conventional method is also highlighted in this paper. The final section discusses the development and possible research trend in WEDM process. © Universiti Malaysia Pahang Publishing.