UK police record around 350,000 missing person reports on an annual basis costing up to £2500 per case. Approximately 38% of these recorded incidents involve individuals who have previously gone missing, many of whom are considered vulnerable and/or at risk. Despite the associated financial and human costs, research into and theory development regarding this significant minority who engage in repeat missing behaviour is extremely underdeveloped. Whilst some attention has been applied to missing behaviour in children, there is very little literature that is concerned with missing adults. Within the proposed research, both quantitative and qualitative methods will be utilised in the form of database analyses and in-depth interviews to investigate the notion of behavioural, cognitive and affective consistencies across multiple disappearances. This study aims to advance our understanding of why such individuals go missing repeatedly, their vulnerabilities and experiences whilst missing, and to provide critical insights for multi-agency prevention and future safeguarding strategies.