In New Zealand, a missing person is defined as: anyone whose whereabouts are unknown, and where there are concerns for the safety and welfare of that person.

While there is a single definition used by police to describe a missing person, there are a variety of different circumstances which fit that description. A missing person may be a victim of misadventure, someone suffering from a health-related issue (i.e. dementia), someone needing time out, or simply someone who is not where they are expected to be.

Missing persons can be of any age, gender, ethnicity, or background and the reasons why people go missing are many and varied.