Dr. Jon Hallberg, standing inside the McGuire Proscenium at the Guthrie complex, is the on-call physician for the Guthrie and other arts organizations. Hallberg is co-founder and medical director of the Center for Medical Humanities and the Arts. He is also heading up an effort to open Mill City Clinic, a health near the Guthrie Theater that he promises will be �the most comprehensive performing arts clinic outside of New York City.�