This chapter addresses the problem of producing and maintaining progress in agent design. New architectures often hold important insights into the problems of designing intelligence. Unfortunately, these ideas can be difficult to harness, because on established projects switching between architectures and languages carries high cost. We propose a solution whereby the research community takes responsibility for re-expressing innovations as idioms or extensions of one or more standard architectures. We describe the process and provide an example — the concept of a Basic Reactive Plan. This idiom occurs in several influential agent architectures, yet in others is difficult to express. We also discuss our proposal’s relation to the the roles of architectures, methodologies and toolkits in the design of agents.