The ORCC building is an 8-storey plus basement, 140,000ft2, concrete and steel structure that has been designed and detailed to be expanded to a total of 10-storeys. The facility contains office, assembly, significant mechanical areas (penthouses), and research/treatment laboratory areas in addition to radiation bunkers on the first floor that are surrounded by mass concrete for shielding purposes. Large 3-storey glazed atriums are located on the ends of the building and are composed of structural steel framing. Additional work, including the construction of a new bunker within the footprint of the existing hospital was performed. As the tower was constructed adjacent to/within the existing hospital, a significant level of effort was required during the design phase to ensure that the owner’s operating concerns were balanced with an efficient structural design and construction methodologies.