Beliefs and assumptions appear in many guises in applied linguistic designs. They illustrate the connections among technical life and the certitudinal sphere. On the norm side, these certitudinal anticipations appeal to designs that are trustworthy. Technical subjects are inspired by steadfastness and commitment to designing credible language interventions that serve others, and that are faithful to reputable design principles. The technical beliefs to which designers subscribe therefore matter. Technical objects, viewed from this vantage point, are vehicles of technical fidelity and security. Language intervention designs should be a celebration of humanity, soundly crafted to inspire and satisfy. [For the complete volume, "A Theory of Applied Linguistics: ?magining and Disclosing the Meaning of Design. Educational Linguistics. Volume 65," see ED672528.]