This paper describes an analysis of some of the challenges facing one portion of the Electrical Smart Grid in the United States - residential Demand Response (DR) systems. The purposes of this paper are twofold: 1) to discover risks to residential DR systems and 2) to illustrate an architecture-based analysis approach to uncovering risks that span a collection of technical and social concerns. The results presented here are specific to residential DR but the approach is general and it could be applied to other systems within the Smart Grid and to other critical infrastructure domains. Our architecture-based analysis is different from most other approaches to analyzing complex systems in that it addresses multiple quality attributes simultaneously (e.g., performance, reliability, security, modifiability, usability, etc.) and it considers the architecture of a complex system from a socio-technical perspective where the actions of the people in the system are as important, from an analysis perspective, as the physical and computational elements of the system. This analysis can be done early in a system's lifetime, before substantial resources have been committed to its construction or procurement, and so it provides extremely cost-effective risk analysis.