Dr. Constantinescu has an active clinical practice at Columbia University Medical Center, including care of children with asthma, cystic fibrosis, and technology-dependent conditions (home ventilation by invasive and non-invasive means, mechanically assisted airway clearance, etc.) He participates in the Muscular Dystrophy Clinic at Columbia, for the management of pulmonary complications of neuromuscular disorders. Through the multidisciplinary Motor Neuron Center at Columbia, Dr. Constantinescu is also involved in clinical research in the area of pulmonary function in neuromuscular disease.