For this comparative analysis we focus on four key health system resources: antiviral drugs (specifically oseltamivir), hospital beds, mechanical ventilators and healthcare workers (doctors and nurses), chosen due to their critical importance for responding to pandemic influenza. These resources, along with over 50 other resource items relating to health system infrastructure, equipment, materials, and human resources, were selected through a systematic literature review and a Delphi consensus process by a panel of 24 experts, as described in [21] . Quantities of these resource items were enumerated during March to September 2009 through questionnaires administered to hospitals and health offices in all districts of each of the six study countries (except Indonesia, where data were collected only from districts in Jakarta and Bali due to the vast geographic scale of the country). Additional questionnaires were sent to ministries of health to capture central stockpiles.