COSA method

How does it work

COSA is aimed at preventing recidivism by addressing some of the key risk-factors for reoffending: social isolation and emotional loneliness.

A Circle provides a medium to high-risk sex offender with a group of trained volunteers, preferably from the local community, who meet with the sex offender (core member in a Circle) on a weekly basis. Volunteers support the core member by modelling pro-social behaviour, offering moral support and assisting with practical needs. They hold the core member accountable by challenging pro-offending attitudes, beliefs and behaviour.

The volunteers are assisted by an outer Circle of professionals. Volunteers report their concerns to the professionals who – when necessary – can take appropriate measures to prevent the core member from reoffending. Volunteers do so not directly, but via a Circle coordinator whose task it is to coordinate the inner and outer Circle and support and supervise the Circle process.

The inner Circle

The inner Circle is constituted of the core member and preferably four to six volunteers. In specific cases a well functioning Circle may choose to go on with less members, but should be able to maintain a sufficient level of personal contact.

The core member is a sex offender who is not completely denying his or her offence, who has been sentenced and has a medium to high risk of reoffending and a high need for social support. He or she is participating in a Circle voluntarily and is willing to subscribe to the Circles goal: no more victims. He or she must be – at least to some extent – willing and able to share information about the offence and personal risk factors with the volunteers. 

The Circle volunteers are recruited from the local community and are carefully selected, screened and trained by the Circle coordinators. The inner Circle should reflect the diversity in the community and be constituted of both male and female members from different ages and backgrounds. Although a Circle should offer core members the opportunity to learn from different perspectives, all Circle volunteers should share some key qualities.

Competent Circle volunteers are able to express empathy and belief in restorative justice. They have good communication skills, are good problem solvers and teamworkers. They have a balanced lifestyle and can handle emotions of self and others. They can set and maintain clear boundaries, and act in a respectful and constructive manner. They also should be able to accept supervision and support from the Circle coordinator. 

Circle volunteers must be insured and get compensated for all costs they make in their function. Some basic safety rules are set up in order to prevent any unnecessary risk. The Circle coordinator is informed about all contacts between volunteers and core member through minutes of Circle meetings and individual contacts (including telephone calls).

The Circle’s goal is to prevent the core member from offending again. It does so through four basic principles:


Main function

The Circle’s main function is to reduce the likelihood of reoffending by providing the core member with a temporary surrogate social network, and to help him or her to establish a supportive social network. Usually a Circle lasts for about one year and a half, but in some cases it may be necessary to maintain a Circle for a very long or even lifelong period.

In all cases a Circle goes through different stages. In order to establish a good working relationship, all Circle volunteers meet a couple of times without the core member. In these meetings they get to know each other, deal with practical issues like day, time and location of the Circle meetings and exchange telephone numbers. After these initial meetings, the core member is introduced to the Circle and the Circle starts to meet on a weekly basis and offers 24/7 support to the core member by telephone.

During the first weeks, starting with the very first meeting, the core members’ offence, offence cycle and risk factors are openly discussed. This part of the Circle process usually lasts about 8 weeks, but this is very dependent on the ability of the core member to understand and share his or her relapse prevention plan. This phase provides the volunteers and core member with a certain basis of shared knowledge that enables open communication (no secrets) and provides volunteers with the information they need for their monitoring function. Although a necessary phase, it is not sufficient to make the Circle ‘work’. It is important that the monitoring function of the Circle is embedded in a trusting relationship, that is built through offering practical and moral support, treating the core member as an equal member of society and acknowledging his or her strengths and responsibilities.

In order to work on the building of a supporting social network of its own, the Circle supports and encourages the development of social and communication skills, for example through modelling behaviour. A Circle may also engage in social activities with the core member in order to offer ‘training on the spot’.  A formal Circle (called phase 1) may evolve into a less formal stage (phase 2) and finally into an informal stage, when the core member, volunteers and the Circle coordinator feel a Circle is no longer necessary, based on a thorough evaluation.

A decision may be taken to continue contact with the core member in an informal way after the formal part of the Circles has completed. This is assessed on a case to case basis and is subject to the governance arrangements and guidelines of individual Circles providers. 

The outer Circle

The outer Circle is formed by the professionals who are involved in the core member’s process of reintegrating society. Often the following organisations and professionals are involved: forensic mental health care (therapist), probation organisation (probation officer) and local police officer, preferably with special assignment to the neighbourhood where the core member lives. Also local welfare organisations or housing institutions may be directly involved in the reintegration process of a specific core member and can be represented in the outer Circle.

Members of the outer Circle have their own professional responsibility and involvement with the core member and operate within the rules and regulations of their organisation and profession. Often one of these professionals is the one who suggests participation in a Circle to the core member and refers him to a regional Circle project. It is good practice to introduce volunteers and professionals to each other at the beginning of a Circle or invite professionals into the Circle during the first weeks. Thus inner and outer Circle get to know each other and are able to exchange views and expectations and set clear boundaries between their distinct roles.

In an ongoing Circle the role of the outer Circle is primarily to support the core member in his functioning within the Circle (as part of their own professional involvement with the core member) and to give advice to volunteers (through the Circle coordinator) on specific topics. They monitor the Circle process through monthly updates from the Circle coordinator.

In case of immediate risk the professionals are informed directly through the Circle coordinator in order to be able to take whatever steps are necessary, e.g. inform justice authorities. Professionals of the outer Circle often are involved in the training programme for volunteers.


Click here for testimonies of people who are involved in COSA.