This article presents the rationale for designing the Slip-Fit Joint. The Slip-Fit Joint eases stress on a patient in donning and doffing an orthosis that crosses the hip joint, such as a HKAFO or a TLSO with a thigh component, especially in a bilateral situation. The Slip-Fit Joint allows a practitioner to separate the orthosis into pelvic and lower sections, and reassemble the two with initial alignment preserved. Once the two are separated, the lower section can be donned independent of the pelvic section. This feature is extremely helpful when fitting bilateral patients or patients whose risk of dislocation while in bed is high. With the Slip-Fit Joint one can also make nearly unlimited internal/external rotational adjustments.