Experimental Analytical substructuring has been a popular field of research for several years and has seen many great advances for both frequency based substructuring (FBS) and component mode synthesis (CMS) techniques. To examine these technical advances, a new benchmark structure is being designed through the SEM Dynamic Substructuring technical division to act as a black-box study for anyone researching in the field. This black-box challenge will include experimental subcomponents and a finite element model to which these experimental results are to be connected. We often know the truth target when completing substructuring research; however, this challenge allows researchers to test their techniques without the aid of a truth measurement. IMAC XXXVII attendees are encouraged to contact the authors in order to join the team designing the black-box hardware and/or eventually have their institution participate in this challenge. The results from the assembled truth measurement will be presented at IMAC XXXIX.