This essay investigates the relationship between programming and design. It exposes and criticizes those views that characterize programming and design as separate and their relationship as linear. Instead, we propose that the relationship is interactive and that the clarification of programmatic and design issues goes hand in hand. During this interactive process both client and architect take significant responsibilities. The design process of the First Unitarian Church of Louis Kahn is an illustrative example. Investigation of the client's reports, of Kahn's and the client's letters, and of Kahn's design proposals exposes the client's contribution and the interaction between programming and design. Our study suggests that clients have the potential to play crucial roles in design and deserve credit.