GSK573719 is being developed as a monotherapy and in combination with vilanterol for the treatment of Chronic Obstructive Pulmonary Disease (COPD). This study will assess the pharmacokinetics and safety of inhaled GSK573719/ vilanterol (VI) and GSK573719 in healthy subjects and in subjects with moderate hepatic impairment. Nine subjects with moderate hepatic impairment will be recruited, together with nine matched healthy volunteers.