While it is difficult to ascertain how extensive the problem of parental substance misuse is in Australia today, international estimates from the USA indicate that approximately 9% of children live in families with parental alcohol abuse or dependence and substance dependence (Office of Applied Studies, 2003). UK estimates of illicit drug use (excluding alcohol) suggest that 2-3% of children in England, and 4-6% of children in Scotland, have parents with drug problems (Advisory Council on the Misuse of Drugs [ACMD], 2003). It seems likely that at least 10% of Australian children also live in families with parental substance misuse (Dawe et al., 2007). However, parental substance misuse rarely occurs in isolation. Parents are often experiencing a range of other problems that affect children's outcomes, including a range of psychological problems that affect mood. Spousal relationships are often strained and, in many families, accompanied by domestic violence. Children of these relationships develop a range of behavioural problems from early childhood and these, in turn, often result in difficulties in settling into the school system. By middle childhood, if little is done, children may be failing to meet minimum literacy and numeracy standards, and engaging in behaviour and conduct problems that make classroom management difficult (see Dawe et al., 2007, for an extensive review of this literature). Given the elevated risk of poor outcomes for children, it is imperative to develop a range of strategies, both at a policy level and in clinical practice, that will reduce the risk of such outcomes. The issue is a complex one and will require a range of treatment responses offered across health, child protection and drug and alcohol services. This brief article will address the issue of identification of substance misuse. How does a clinician determine if a parent is a problematic substance user within the context of routine clinical practice? For those in drug and alcohol treatment agencies, this is a relatively straightforward matter, as such information is clearly core business. But what of those in agencies who come into contact with multi-problem families but are not directly presented with a substance use issue (e.g., general practice or child health services)? Alternatively, how does a practitioner who learns of parental substance use gauge whether this use may be adversely affecting children?