In my experience, novel ideas for 3D interaction techniques greatly outpace developers’ ability to implement them, despite the potential benefit of these ideas. I believe this is due to the inherent implementation complexity of 3D interfaces, without sufficient support from methods and tools. Believing a developer-centric representation could overcome this problem, I investigated developer practices, artifacts and language. This resulted in the theory of Concept-Oriented Design and Chasm, a prototype realization of the theory. The key feature of Concept-Oriented Design is its use of developer-centric representations to create a multi-tiered implementation, ranging from an envisioned behavior expressed in conversational language to low-level code. Evaluation of Chasm by domain experts and its use in multiple case studies by volunteer developers has demonstrated that Concept-Oriented Design in Chasm addresses many of the problems of 3D design and development.