Modular-functional decomposition is a fundamental tenet of computer science. Cognitive robotics, with strong roots in cognitive science and biology,replaces modular-functional decomposition with a more opportunistic approach. Nonetheless, we can extract heuristics with both analytic and synthetic power: architectural principles for postmodular systems. This paper describes three postmodular principles: imagination, shared grounding, and incremental adaptation. It briefly discusses examples of each drawn from existing systems. The paper concludes with an illustration of these three principles used in concert to build a system that progresses first to hand-eye coordination, then to planned complex reaching, and finally to shared attention.