This study quantifies the costs and benefits of Integrated Environmental Strategies (IES) of reducing air pollutants and greenhouse gas (GHG) emissions at a minimal cost in the Seoul Metropolitan Area (SMPA) for the year 2014 and compares with current air quality management plans and greenhouse gas (GHG) mitigation plans. The results estimated health benefits from prevention of premature mortality under the IES scenario as 14 trillion Korean won (won) and associated cost as -3.6 trillion won, yielding total benefit, difference of benefits and costs, of 18 trillion won. With the inclusion of benefits from GHG reductions, the total benefits result in 147 trillion won. The difference of human health benefits and costs of air quality management plan and GHG reduction strategies result in 14 trillion won and 8 trillion won, respectively. The research shows that benefits of integrating air quality management and GHG reduction measures are greater than those obtained by air quality management and GHG reduction measures individually. (C) 2011 Elsevier Ltd. All rights reserved.