This paper develops such common vision through a system atic approach based on an understanding of grid reliability challenges as well as fundamental impacts of the evolving smart grid resource mix. We first provide an overview of the reliability challenges and then present a critical review of the salient reliability impacts of the four resource types identified above. We observe that an ideal mix of these resources that flattens net demand would eventually accentuate reliability challenges even further. Meeting these challenges requires a gridwide IT infrastructure that provides coordinated monitoring and control of the grid. An architectural framework for such infrastructure should support a multitude of geographically and temporally coordinated hierarchical monitoring and control actions over time scales ranging from milliseconds to operational planning horizon. Such capability is necessary to take full advantage of the modern measurement technologies (e.g., PMUs) and control devices (e.g., FACTS). This paper presents such architecture to serve as a concrete representation of a common vision that fa- cilitates the development of various components of the IT infra- structure as well as the emergence of necessary standards.