Early in 2001, Australia experienced an acute heroin shortage that forced the price of heroin up and the purity of heroin down. The result was an immediate drop in the rate of fatal heroin overdose and a slower but nonetheless substantial drop in levels of property crime. The fall in property crime has been widely attributed to a fall in heroin use. One problem with this explanation, however, is that property crime rates continued to fall long after heroin use had stabilised, albeit at a lower level. This bulletin reports the results of a systematic analysis of a number of crime-relevant factors that changed over the same period that property crime rates fell. The results indicate that the downward trend in property crime was assisted by the fall in heroin consumption, but other factors also played an important role. These include a real increase in average weekly earnings, an increase in the number of heroin users returning to treatment, an increase in the imprisonment rate for convicted burglars and, possibly, a fall in long-term unemployment.