A careful analysis of the current status of business process “as-is” state will enable lesser or controllable deviation in the ERP enabled business process “to-be” state (Scheer, Habermann, 2000). This analysis will decide on the extent of customization required to fine-tune business processes to ERP prescribed processes and vice versa depending upon the maturity of the organization. The configuration-vs-customization tradeoff will impact the measurement of operational efficiency from an ERP system and return-on-investment. SMEs is skeptical on the return-on-investment from strategic IT initiatives like ERP because they are not competent to measure and evaluate the performance of business post implementation of ERP. Performance management here becomes an integrated aspect of ERP success. Both tangible and intangible aspects expected out of ERP enabled business should be taken into consideration for performance management. Taxonomy of critical factors will serve as a reference for realizing and maximizing the benefits of ERP (Al-Mashari et.,al, 2003). Such a reference model will boost the confidence of SMEs in approaching and adopting ERP.