Virtualization provides opportunities to reduce complexity, improve service levels to the business and lower capital and operating costs to provide and maintain IT infrastructure. Over the past five years many organizations have specifically deployed VMware infrastructure software on industry standard systems to significantly reduce their hardware, data center, and operational costs--many report 70-80% cost savings, and 3-6 month ROI periods--while achieving unexpected gains in operational flexibility, efficiency, and agility.

Read this IBM paper that lays out the benefits basics of virtual infrastructure technical design, project planning, scoping, and implementation.