This document provides guidance on building a business case for virtualization. It outlines steps to define goals, benchmark current costs and performance, analyze organizational impact, define a virtualization solution and service model, plan migrations, and conduct a financial analysis. Key recommendations include gathering both costs and benefits of virtualization, calculating metrics like ROI, NPV and IRR, and considering per unit costs of virtual versus physical infrastructure to strengthen the financial justification. The overall message is that virtualization transformation requires more than just technology and the financial case for it is strong when all factors are properly analyzed.