High speed milling (HSM) is one of the emerging cutting process having tremendous potential not only in increased metal removal rates but also in improved surface finish, burr free edges, dimensional accuracy and a virtually stress free component after machining. Defining high speed machining sometimes is controversial, since the actual cutting speed that can be achieved depends on the workpiece material, the type of cutting operation and the cutting tool material used. The full understanding of this technology requires a structured process model to describe the high speed milling process which allows for the prediction of process output parameters.The paper focuses on generating a computer model of modular structure complete with an integrated input parameter database for high speed milling based on theoretical considerations. This model is applied to analyse published data and it was revealed that these results were controversial with regards to machinability indicators, e.g. cutting force, energy, temperature and the like. Therefore the research has been extended to the experimental measurement and analysis of cutting forces, and removal rates with particular consideration being given to workpiece and cutting tool properties. The results obtained from these experiments correlate well with the process parameters predicted by the computer model. The developed computer model allows for process parameter selection of HSM process relevant to the aerospace industry, but the considerations can be extended to the milling of difficult-to-machine materials.