Additive manufacturing enables the design and manufacturing of complex structures with multiple unique parts. While printed parts can be easily manufactured, the assembly of intricate projects still remains a challenging endeavor. This chapter discusses how 3D Printing gives way to custom connections and careful design of assembly sequences, including the systematic organization of the information, physical parts labeling, joinery strategies, and the creation of virtual assembly models. The project AirTable serves as a case study to demonstrate this approach through a built project.