This document presents the work performed under the contract SMART 2016 / 0029 “Certification schemes for Cloud Computing” from March 2017 to March 2018. It aims to provide the European Commission with evidence of what is retaining the adoption of cloud computing as well as to why cloud service providers are not getting certified in the existing schemes that are available. The study consists of the following major parts: * Analysis of the barriers that are hindering the adoption of cloud computing certification schemes, including market penetration, a gap analysis of five certification schemes, costs and approaches for obtaining a certification, initiatives carried out by the public sector as well as by the private one, in collaboration or not with the public one; * Minimum set of requirements that a EU-wide certification scheme should cover; * Analysis of the scenarios the EU could be led to depending on the actions taken; * Conclusions on the findings.