Compliance is the ease with which a change occurs. For pulmonary compliance that means the relative amount of pressure needed to make a change in volume. As such emphysema and COPD are characterized by decreased compliance because more effort is needed to change the same amount of volume. The statement that Emphysema and COPD represent conditions with decreased compliance is incorrect and is probably confusing the increased lung volume that often accompanies those conditions. High lung compliance (low effort for the amount of volume change) is associated with healthy lungs.