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The Dutch Probation Service and Avans University of Applied Sciences consider it important that COSA have a scientific basis. The Circles-NL programme office conducts research on the functioning and on the effect of the Dutch circles.

European Handbook

The project Circles Europe, Together for Safety (2009-2011) has developed a standard for future implementation of Circles in Europe. It is very important to monitor the quality of implementation. Based on experiences in the United Kingdom, Belgium and The Netherlands, a European Handbook has been written. Within the project Circles4EU (2013-2014) the handbook was revised. Both projects were made possible with funding by the European Commission. The European Handbook is available in English and worth reading for researchers and professionals in other European countries that consider to start working with COSA. For a free copy, please send an e-mail to circles-nl@avans.nl citing 'European Handbook' and your contact details.

The European Handbook (revised edition) is now available as free download (pdf).

You can read more about the European project on www.circles4.eu 

Publication in SAGE Journals. Helping Sex Offenders to Desist Offending. The Gains and Drains for CoSA Volunteers - A Review of the Literature. By Mechtild Höing, Stefan Bogaerts and Bas Vogelvang. Download available.

Publication in Journal of Forensic Psychology Practice, Volume 13, Issue 4, 2013. Circles of Support and Accountability: How and Why they work for Sex Offenders. By Mechtild Höing, Stefan Bogaerts and Bas Vogelvang. Download available (max. 50). View by this link.

Publication in Eurovista vol.2, No.2
Circles of Support and Accountability, and community reintegration for those at risk of sexually reoffending. August 2012. By Stephen Hanvey and Mechtild Höing.


COSA in the Dutch context

A special study looked at the adaptations that are necessary for the Dutch context to make COSA's implementation a success in the Netherlands. Partly on this basis, preparations were made to launch the first pilot circles.

Download the full text of the Adaptation Study (PDF 0.6 MB) (in Dutch)

Interim report of the process evaluation

The main research questions in this implementation study are:

  • To what extent are the requirements for a successful implementation met at the start of the project, as described in the theoretical model?
  • To what extent can COSA be executed in practice as intended?
  • To what extent and in what manner will the result objectives mentioned above be achieved?

This report provides an interim result: it describes the results of the points mentioned above based on the experiences from the preparatory and initial phases of the pilot (through February 2010).

Download the executive summary of the interim report (in Dutch)  

Implementation study pilot phase

The implementation study on the pilot phase of Cirkels in The Netherlands has been completed in Spring 2011. The question if COSA can be implemented successfully in the Dutch context can be answered affirmative.  It appears to be possible to recruit and select sufficient volunteers and core members, and to build a national and regional project organisation, that supports the effective functioning of circles. However, some improvements can still be made. The implementation study shows which factors contribute to a successful implementation of Cirkels.

Download the executive summary of the implementation study (in English)

Cosa in Belgium

Part of the project Circles Europe Together for Safety is a study for the adaptations needed in the Belgium context. At the moment Belgium is ready to introduce the first pilot circles and make this implementation succesfully. Download the summary of the Belgium study here (pdf, in English)