The Children's Hospital of Philadelphia (CHOP) began its expansion of the Leonard and Madlyn Abramson Pediatric Research Center building in 2001. Located in West Philadelphia, this research center is acknowledged as a leader in the advancement of basic and clinical research that will lead to improved healthcare for children worldwide. Working with L.F. Driscoll, Co., Samuel Grossi & Sons fabricated and erected 700 tons of steel for a vertical expansion of the structure. A total of eight new floors were added to the existing five story building, resulting in 120,000 more square feet of space.