To build a business case for moving systems to the cloud, you first need to understand what your existing infrastructure actually costs. There's a lot to factor in: obvious things like the cost of running data centres, and extras such as leased lines. The cost of physical hardware – servers and details of specifications like CPUs, cores and RAM, plus the cost of storage. You'll also need to calculate the cost of applications, whether you plan to dump them, re-host them in the cloud unchanged, completely rebuilding them for the cloud, or buy an entirely new SaaS package. Each of these options will have different cost implications. The cloud business case also needs to include people costs (often second only to the infrastructure costs) and more nebulous concepts like the benefit of being able to provide new services faster. Any cloud business case should also factor in the potential downsides, including the risk of being locked into one vendor for your tech infrastructure (see multi-cloud, above).Cloud computing: How to build a business caseCloud computing: What it's like to make the move