The advent of the Cloud has leveraged a number of challenges, both for customers and service providers. Companies willing to embrace the new paradigm must face some entrance barriers, such as security, privacy and trust concerns, vendor locking risk, legal issues, etc. While service providers may work to minimize these barriers, they must be especially careful when defining what may constitute the most crucial aspect for the success of their offerings: the business model. Different incarnations of the cloud (IaaS, PaaS, and SaaS) add to the possibility of offering public or private solutions, or even federated models. On top of this is the billing strategy: the ubiquitous pay-per-use approach (either in its most common post-paid incarnation, or in a novel pre-paid version) is only the starting point for a wide range of innovative solutions, including bundling or QoS considerations, which European project VISION Cloud is tackling as part of its research efforts. This chapter aims to provide a comprehensive discussion on the most relevant business factors that the Cloud confronts.