This study established the existence of itinerant Eastern European crime groups traveling significant distances to commit property crimes in Belgium. Data on the nationality of property offenders who had engaged in multiple and co-offending in Belgium shows that the proportion of Eastern European offenders in the total sample (n=64,409) was only 11.3 percent, compared with 67.1 percent who were Belgians and 21.5 percent who were of other nationalities. A measure of the mobility of property offenders who had engaged in multiple offending and co-offending was found to average 14.6 km from the offender’s residence to the location of the property offense. Criminals who had both multiply offended and engaged in co-offending traveled an average of 21.4 km from their residences to commit their crimes, compared with a distance of only 14.3 km for the other criminals in the sample. By combining mobility and nationality, the study found that Eastern European multiple offending co-offenders had traveled an average of 37.4 km to commit their crimes, compared with only 18.4 km for Belgian multiple co-offenders. Future research must determine why these groups travel such distances to commit their crimes and how they can be effectively countered. The study obtained police statistics on serious property crimes (property crimes with aggravating circumstances, such as burglary) committed in Belgium over a period of 5 years. The data analysis focused on the nationality and mobility of those engaged in habitual offending and co-offending. 2 tables and 23 notes