While it is widely acknowledged that cloud computing has the potential to transform a large part of the IT industry, issues surrounding the adoption of cloud computing have received relatively little attention. Drawing on three case studies of service providers and their customers, this study will contribute to the existing cloud technologies literature that does not address the complex and multifaceted nature of adoption. The findings are analyzed using the adoption of innovation literature as a lens to reveal how technological, organizational and environmental factors impact cloud adoption. Our conclusions reveal that factors impacting cloud adoption tend to be psychological as well as technical, and some recommendations are put forward for future research.