Data Envelopment Analysis (DEA) is a powerful method widely used in the evaluation of performance of Decision Making Units (DMUs). These can be business units (for example points of sales, bank branches, dealers, franchisees), government agencies, police departments, hospitals, educational institutions, and even people (DEA has been used in the assessment of athletic, sales and student performance). xlDEA provides this sophisticated analysis in the most suitable environment, the MS Excel. It produces extensive results for the main DEA models used today, and automatically creates Excel charts. In view of the analyst's need to present his/ her results in a professional way, XLDEA also supports the production and customization of Macromedia Shockwave Flash charts which can be easily transferred to any browser-based environment.