This paper explains the rationale and overall concept for defining a risk-based approach to the design and technology usage of systems to achieve a set of differentiated business availability and recoverability classes. It provides an overview of the various dimensions being taken into consideration and also elaborates on the aspects that drive the differentiation of best practices or technical capabilities used to achieve the different classes.The paper elaborates on the generic process aspect of assessment of existing systems. It explains how we would utilize this foundation to establish guidelines for applications, the underlying technology and infrastructure, as well as the operational set-up.The principal motivations for the availability and recoverability classification are i) to improve the ability to fulfill the required levels of availability and recoverability and ii) to optimize the investment and operational cost. Businesses will classify their availability according to the distinctions defined here which will limit the extent of high cost critical applications. Additionally, applications will architect their designs for lower cost methods of achieving the desired level of availability.There is no cookie-cutter formula to accomplish these goals. Only if all pieces and building blocks of the architecture are designed from the beginning to fit to each other, will the entire system achieve optimized service availability levels.