In the present book results of experimental investigation on machinability of Ti-6Al-4V are presented. Design of experiment based prediction models for machining response such as surface roughness, cutting force, MRR, tool wear, power consumption, and residual stresses are developed. RSM is used for creating list of experiments for turning and milling operations. Furthermore, various optimization techniques such as RSM optimizer, GA, TLBO, JAYA are implemented for better machining response. In an additional study related to use of new cutting fluids, performance of multi walled carbon nano tubes (MWCNTs) based nano fluid was also evaluated in machining of Ti-6Al-4V. Performance evaluation was done on the basis of cutting force, tool wear and surface roughness and results were compared with conventional coolant (Blasocut 4000) and dry machining.