For the estimated 12.7 million people with chronic obstructive pulmonary disorder, the third leading cause of death in the U.S., innovative research efforts in the field of tissue regeneration hold promise. In end-stage lung disease, transplantation is sometimes the only viable therapeutic option, but organ availability is limited and rejection presents an additional challenge. New research focuses on lung tissue bioengineering, which involves the use of a scaffold — or framework — of lungs from human cadavers to engineer new lungs for patients with end-stage disease.