This report presents an introduction to Cloud computing, with internationally adopted definitions, and some additional clarifications from real life experience. It provides an explanation of the driving forces behind Cloud computing as well as some data with regards to the state of the business, and sets forward the opportunities and challenges for Cloud adoption. The report goes into detail on the four core challenges that need to be addressed to lead to Cloud adoption: Innovation, Infrastructure, Skills and Awareness, and Trust. It also includs insights from countries that have adopted Cloud and provides guidance on Cloud computing policy making.