1. A system for selecting a preferred design architecture for a multi-tiered architecture based on a service specification, an infrastructure specification, and service requirements, said system comprising: a computing device having a computer storage medium, said computer storage medium having stored thereon an automated design generator for receiving the service specification and the infrastructure specification and for automatically establishing a plurality of candidate designs in a computing device readable and explorable format based on said service specification and said infrastructure specification; and an availability evaluation engine configured to receive the plurality of candidate designs and provide availability estimates for the received plurality of candidate designs to the automated design generator; wherein the automated design generator iteratively evaluates the plurality of candidate designs in combination with the availability estimates to establish the preferred design; and further wherein said computing device readable and explorable format is partitionable and comprises at least one from a group comprising: an attribute value expressed as an ordered set; an attribute value expressed as a function; a scalability attribute; a scope of fault attribute; and an availability mechanism.