The author introduces the playful-tension model, a new theoretical concept, to harmonize the gap in play design between general play theory and its actual use in designing playthings. By synthesizing a broad selection of general play theory into a single theoretical concept, the playful-tension model accentuates the delicate interplay of what he calls "handleability" and "unhandleability" as a primary concern for play designers. He asserts that the contribution of the playful-tension model lies in its ability to unify the complex and scattered landscape of play studies into a high-level middle ground metatheory that empowers play designers and inspires them to a more deliberate practice.