Continuous improvement in the server technology performance-price ratio has caused many organizations to simply dismiss the need for accurate workload and resource planning efforts. In the current economic climate, infrastructure optimization and operational efficiency are once again priorities, albeit for different reasons than pure hardware optimization. Under the auspices of this real market need for IT operational efficiency, hardware and systems management software vendors are promoting modular computing architectures as silver-bullet solutions, fueled by the promise of virtualization. The reality is that while these computing models may provide enabling technologies in the pursuit of operational efficiency, they only epitomize the need for a better and reliable capacity management process that would benefit from taking full advantage of these computing models. As the new models of virtualization, platform-as-a-service (PaaS), and software-as-a-service (SaaS) become more successful, a new set of decision-making tools is needed, and vendors should arm themselves with a new integrated tool set to take advantage of this opportunity.