ABSTRACT: Triage processes are commonly used to manage the interface between demand for, and supply of, health services. This dimension of service provision is particularly pertinent for mental health services in Australia, where demand outweighs services available. This paper draws on the experiences of using participant observation to explore mental health triage processes. Findings highlight the complexities of the researcher role and benefits of using an ethnographic approach to explore mental health triage patterns. Insider participant observation brings many challenges but also, in this study, enabled the researcher to uncover some roles and processes underpinning triage decisions in mental health services.