More than one-half of the 2.4 million deaths that will occur in the United States in 2004 will be immediately preceded by a time in which the likelihood of dying can best be described as "ambiguous." Many people die without ever being considered "dying" or "at the end of life." These people may miss out on the opportunity to close important relationships and make financial and legal arrangements that can benefit themselves and their survivors. They may inadvertently forgo palliative care that is available to comfort them physically, emotionally, and spiritually. This article calls for a broader conceptualization of the end of life to include not just the time when death is foreseeable, but also the time when people are at a greatly increased risk of death, although the timing is highly uncertain. Social workers have much to offer people affected by the "ambiguous dying syndrome."