Acquiring an ERP system is one of the most risky, tedious and complex decision making activity for any organization. It has been widely reported that selecting an inappropriate ERP is a one of the major reason for its implementation failure. In this present paper, we develop a new ex-ante evaluation method for ERP system tailoring and selection. The proposed method, called SEVALERPS (Systematic Evaluation of ERP Systems), is basically elaborated to help organizations, especially large ones, to better customize and evaluate the potential ERP solutions in order to choose the ones that make their best requirements’ tradeoff. SEVALERPS relies on many sound mathematical techniques to handle various evaluation aspects: 0-1 linear programming to choose the best ERP tailoring scenarios, MACBETH to voice out the preferences of the selection team in both qualitative and quantitative way, and the discrete Choquet integral to address interdependencies that might exist among evaluation criteria.