Dr. Knabe's private practice was in her combination office-home in the Delaware Flats building. This 1911 city directory listing indicates that she was a physician whose address was apartment 2 at 503 North Delaware Street (the address of the Delaware Flats in 1911). The other listing is for her older cousin, Auguste Knabe, who had immigrated to Indianapolis a few years before Helene. The listing shows that she was a teacher at Public School Number 33 and a boarder at 1151 Bates Street. Helene Knabe also had boarded at that address before moving to the apartment in the Delaware Flats.

R. L. Polk and Company's Indianapolis City Directory for 1911, Image courtesy of IUPUI Center of Digital Scholarship