In many countries, there is increasing interest in early intervention strategies to assist people who are experiencing gambling-related problems. Central to these discussions is whether it is possible to identify problem gambling and/or risky behaviour in situ before gamblers formally seek assistance. This paper provides a review and critique of the small amount of published literature relating specifically to behavioural indicators and their practical application. It concludes that, while there is general agreement concerning the range of indicators that could be used, the process of identification remains difficult in practice. Multiple indicators are usually required to make reliable identifications; the nature of indicators will vary depending on the mode of gambling (land-based vs online), and venue staff employees usually have insufficient opportunity to obtain enough information to make judgments. The potential value of combining behavioural information with electronically monitored gambling data is discussed as a possible future strategy for enhancing the effectiveness of identification processes.