PROJECT SUMMARY/ABSTRACT Year 5 of the Intermountain West Clinical Site (University of Utah) for the Undiagnosed Disease Network will be focused on completing the evaluation of participants enrolled by June 30, 2022. Because of the pause in accepting participants by other sites, the Intermountain West Clinical Site has been receiving in year 4 a several-fold increase of applications from a wider geographic catchment area than was originally assigned to the site. This increased amount of effort in year 4 will translate in increased number of participants accepted in year 4 and having to be evaluated in year 5. The evaluation will follow the UDN protocols with the goal in year 5 of completing all evaluations accepted in year 4. The Intermountain West Clinical Site will bring the team, experience, resources, and institutional support to advance the shared goal of UDN – improve the diagnosis and management of difficult-to-diagnose and new diseases—efficiently, equitably, and sustainably.