"NIOSH is developing a voluntary roster containing information about thousands of response workers who are participating in the recovery efforts to create a record of those who have participated in cleanup activities and a mechanism to contact them about possible work-related symptoms of illness or injury, as needed. The information collected in this roster would be vital for possible future studies to determine whether health conditions that may develop are associated with occupational exposures during the cleanup. In an attempt to reach all cleanup workers, a rostering program is being administered in English, Spanish, and Vietnamese. NIOSH has also extended the rostering effort to include federal workers and state and county workers who have received the required safety training and who are responding in the event. Through our rostering efforts to date, we have already captured information from more than 20,357 workers responding to this event. More information including copies of the rostering form are available on the NIOSH website.