Since the 1990s,the implementation of Enterprise Resources Planning ERP became a key to enter the global business. Unfortunately, the price of this key is extremely high. Research is showing that its' cost may reach $100M for only one organization. Furthermore, there are lot of horror stories happened to some companies in the implementation phase. Therefore, ERP implementation became a hot topic for lot of studies in the last 20 years. However, the research didn't pay the same attention to the post-implementation stage and how to assess its' success. Many firms even don't have an assessment model for their Return On Investment from the investing in ERP. The author clarified in this book the way to enhance the productivity of the Implementation Stage and a model to assess the Post Implementation Phase. The author used an assessment model based on the Balanced Scorecard Approach in the Saudi organizations. 22 KPIs distributed in his questionnaire based on the Four BSA dimensions; financial, customer, learning & growth, and internal process. The findings proved that Financial Benefits were the lowest achievements after ERP Implementation because enterprises aren't tracking ROI monthly