You have designed a model per your Core Domain’s Ubiquitous Language. You’ve developed ample tests around its usage and correctness, and it works. But how do other members of your team design the areas of the application that surround the model? Should they use DTOs to transfer data between the model and the user interface? Or are there other options for conveying model state up to the presentation components? How do the Application Services and infrastructure work? This chapter addresses those concerns using the now familiar project to convey available options.