The study showed that on 30 June 2003, there were 23,555 prisoners in Australian jails (ABS 2004). Of these, seven per cent (1,594) were women, an increase of 109 per cent since 1993. Of the 812 male and female prisoners whose most serious offence involved deception or a related offence, 21 per cent were female, representing 11 per cent of the total female prison population, compared to three per cent of men in jail for the same category of offence. Fraud is a significant component of female offending, and examining the dynamics underlying serious fraud is important if security managers are to understand the broader issues of gender difference in patterns of offending and imprisonment. Using unique data collected by the Australian Institute of Criminology, the study demonstrates that, contrary to the previous welfarist and needs-focused explanations of fraud, women also are involved in more sophisticated and planned cases of serious fraud.