In the nineteenth century in the Netherlands, tramps and beggars were sent to Veenhuizen to work there as a form of punishment and rehabilitation. To investigate the background of these banished men, the authors drew a systematic 5% sample out of 6.000 men who were banished between 1896-1901. Using information from the so-called ‘signalements’-cards that were compiled, the authors found that the Veenhuizen men were not uneducated, unskilled workers, but on the contrary, often had some kind of (semi-)skilled profession. Many did not have a permanent abode, and only a few had (ever) been married. At on average 45 years of age, the Veenhuizen convicts were old for the era they lived in. As such these men lacked and had probably at some point in their lives lost societal as well as social ties, and had gone adrift.
Recidivism was high. While the Veenhuizen measure may have been effective in delivering society from the blemishes that these men represented, but in general it didn't turn these men into fully participating citizens.

What do we know about radicalization and radical groups? This thematic issue focuses on these questions and this introduction sketches the outlines of the subject. Many researchers studied this subject from different angles, using various research techniques and sources of information.