The increasing adoption of software-as-a-service (SaaS) across the world requires software vendors to look for a more efficient way of deploying business applications on multitenant platforms. Because independent software vendors (ISVs) are starting to realize the value of platform-as-a-service (PaaS) offerings, Forrester has applied its sizing methodology for emerging markets to this new platform market. A 6-step approach provides a reproducible sizing tool and can be updated by vendor strategy professionals depending on the economic climate. Based on the current assumptions, the PaaS market will grow over eight years to a size of $15.2 billion in total volume.