In this paper Smart City initiatives will be explored from the perspective of the enabler factors required for such intitiatives to be successful. In detail, we see smart cities made of five collectively exhaustive dimensions, i.e. Technology, Social Infrastructure, People-Private-Public Partnerships, Governance and Management, and Smart Information Services. Thus, after a brief introduction of the domain of analysis, the starting point will be a systematic review of the literature. Then we will describe each perspective explaining why and how it has to be considered. Finally we will propose some discussions, in particular around the applicability of our framework for embedded assessment and measurement tools (e.g. Balanced Scorecard).