The NYC Department of Health and Mental Hygiene, in collaboration with Healthix, designed the NYC Emergency Patient Search (NYCEPS) Portal to assist the public in city- and state-wide emergencies. After a mass casualty incident, a key concern is locating and assuring the safety of loved ones who may have been aﬀected and cannot be easily reached or located. NYCEPS queries real-time patient data through Healthix, particularly information from encounters at acute care hospitals and nursing homes – all with the intention of facilitating family reuniﬁcation. NYCEPS staﬀ can help search for a missing person who may have been treated at a New York City hospital, thereby giving families one place to call to inquire about a family member. This potentially reduces the overwhelming number of phone calls to individual healthcare facilities which are already overburdened in times of crisis.