"The Belgian prison population increased with 19.7% between 2000 and 2009 and this increase continues over the period 2009-2011 (Aebi and Delgrande 2011, p. 39). Where on the first of September 2009 the total number of prisoners is 10,901 (Aebi and Delgrande 2011, p. 39), the total number of prisoners on the first of September two years later, in 2011, is 11,913 (Directorate-general of Penitentiary Institutions 2011b). Belgium is not an exception and is confronted with the problem of prison overcrowding (Aebi and Delgrande 2011, p. 38). Especially the category of sentenced prisoners and prisoners on remand is increasing (Maes et al. 2011))."

Source

Deprez, Nathalie, et al., "2011 National Report (2010 data) to the EMCDDA by the Reitox National Focal Point" (Brussels, Belgium: OD Public Health and Surveillance, Scientific Institute of Public Health, October 2011), WIV-ISP/EPI REPORTS N° 002, p. 222.
http://www.emcdda.europa.eu/a…