Although needs assessment surveys are carried out after many large natural and man-made disasters, synthesis of findings across these surveys and disaster situations about patterns and correlates of need is hampered by inconsistencies in study designs and measures. Recognizing this problem, the US Substance Abuse and Mental Health Services Administration (SAMHSA) assembled a task force in 2004 to develop a model study design and interview schedule for use in post-disaster needs assessment surveys. The US National Institute of Mental Health subsequently approved a plan to establish a center to implement post-disaster mental health needs assessment surveys in the future using an integrated series of measures and designs of the sort proposed by the SAMHSA task force. A wide range of measurement, design, and analysis issues will arise in developing this center. Given that the least widely discussed of these issues concerns study design, the current report focuses on the most important sampling and design issues proposed for this center based on our experiences with the SAMHSA task force, subsequent Katrina surveys, and earlier work in other disaster situations.