The Missing Person Category Matters

Gary Foo’s Five Categories of Missing and Lost Persons

Developed and taught by Gary Foo before first publication in Emergency Response and Search & Rescue: An Operational Book (2009). Revised second edition: 2012, pages 191–202 and being updated in the 2027 3rd edition.

Have you ever separated from a family member in a shop and spent several minutes looking for them? You know what they look like, what they are wearing and where you last saw them. Finding them can still take time.

Now consider the same uncertainty across a town, a river system or the damaged buildings after a disaster. Understanding how someone became missing helps responders consider where they may be, what evidence matters and how to approach the search. Time, weather and movement can change both the search area and the available clues.

Five Categories, Different Search Problems

“Missing person” describes a report, but does not explain the circumstances of disappearance. Terms matter for professionals.

Gary Foo’s framework identifies five operational categories to help structure that first assessment. They are working hypotheses to investigate and revise as information develops.

These categories may overlap and change as evidence develops. 

“Missing person” remains the general reporting term; “Missing” above is its narrower use within this framework. “Absent” does not indicate low risk or reduced urgency. Professionals and Specialists like Emergency Services and SAR Team members know that terms matter. Circumstances and profile matters. Lost Person Behaviour matters. 

Category, Subject Profile and Detectability

The category is one part of the operational picture. Effective planning also considers the subject’s individual profile, including their health, cognition, mobility, experience, routines and circumstances.

Detectability asks a different question: if the person is within the area being searched, how likely are responders to notice them? Concealment, visibility, clothing, debris and the ability or willingness to respond can all affect detection.

Earlier research examines the varied circumstances of going missing (Payne, 1995; Biehal, Mitchell and Wade, 2003). Koester’s Lost Person Behavior (2008) provides incident-based subject profiles relevant to search planning. Foo’s framework brings attention to the mechanism of disappearance alongside those individual characteristics.

Applications Across Emergency Response

Police missing-person response: Disorientation, deliberate departure and third-party removal raise different investigative questions and search priorities.

Flood response: A person displaced by moving water presents a different search problem from someone who walked away. The path of the water and potential stopping points become relevant to the operational picture.

Urban search and rescue: Following collapse, responders must consider who evacuated, who may remain inside and who may have been trapped or displaced. The framework complements established USAR assessment and search methods.

Many searches do not result in a find or rescue. Many rescues begin with a known casualty location and require no initial search.

About Gary Foo

Gary Foo, ECFO, CEMC, MCPara, FInstLM, FCollT, is an emergency services professional, leader, educator and author with more than four decades of experience across policing, fire and technical rescue, paramedicine, search and rescue, disaster response and incident management. A former sworn police officer in the United Kingdom and Canada, he is a serving Fire Chief and Fire Commissioner and disaster Paramedics. His experience includes international operational response with coordination by the UN in the INSARAG framework and emergency services capacity building and training.

References and Further Reading

1. Foo, G. (2009; revised 2012). Emergency Response and Search & Rescue: An Operational Book. Second edition, pp. 191–202. ISBN 978-0-9563988-5-7. Original source of the five-category framework.

2. Payne, M. (1995). Understanding “Going Missing”: Issues for Social Work and Social Services. British Journal of Social Work, 25(3), 333–348. Read more

3. Biehal, N., Mitchell, F., & Wade, J. (2003). Lost from View: Missing Persons in the UK. Policy Press. Publication record

4. Koester, R. J. (2008). Lost Person Behavior: A Search and Rescue Guide on Where to Look for Land, Air, and Water. dbS Productions. Subject profiles

5. Ferguson, L., & Gaub, J. E. (2023). Training police search and rescue teams: Implications for missing persons work. Criminology & Criminal Justice, 23(3), 431–449. Read the article

6. INSARAG (2020). INSARAG Guidelines. View guidelines

These references provide research and operational context. They do not constitute validation of the five-category framework or a measured improvement in find rates.

Framework and original published work © Gary Foo.