Presently disclosed is a process and system for assembly-based parametric modeling having a single design environment in which the parts, components, and assemblies thereof may be designed concurrently. In embodiments of the present invention, every assembly has a deterministic parametric history supporting both top-down and bottom-up assembly design methodologies. Top-down components may be built in place, reducing the user interaction required to define the attachment and movement characteristics of the assembly. Bottom-up components may be inserted into an assembly using a parametric Insert Component Feature. The process and system also provides the ability to parametrically define the shape of an assembly in multiple orientations that still regenerate deterministically.