Ballinger is an architecture/engineering firm, one of the first in the United States to merge the disciplines of architecture and engineering into a professional practice. The firm's single office in Philadelphia, Pennsylvania houses a staff of over 200 people comprising three architectural studios, two multi-disciplinary engineering studios and an interiors studio. Ballinger is one of the largest architectural firms in the Philadelphia region and known for its work in academic, healthcare, corporate, and research planning and design.