The high number of missing person reports that occur globally each year highlights the need for research in this academically neglected field. This research focuses on establishing whether there are different scenarios or behavioural themes that consistently appear in missing person cases in Spain, which could assist the police investigation process. A representative sample of 341 missing person police reports was collated and up to 27 behaviours, which occur during the disappearance, have been codified, as well as circumstances surrounding the case. Through multidimensional scaling four behavioural themes have been identified: intentional-escape, intentional-dysfunctional, unintentional-accidental, and forced-criminal. These findings entail implications, both in terms of prevention and in the scope of police investigations. Specifically, this research is considered a key step in the development of: (a) a predictive risk assessment system for harmed or deceased outcomes, and (b) in-depth review of forced-criminal disappearances that concur with homicide.