The Centre for Effective Dispute Resolution (CEDR), the largest mediation provider in the UK, is in talks to exclusively lock-in a group of its top mediators, it has emerged.

Legal Week has learned that CEDR has already reached an agreement in principal with around 30 of its top mediators to work on a preferred, exclusive basis.

The body, which has 130 registered mediators and regularly works with 60, hopes to next year sign formal contracts that would restrict mediators from taking referrals from other mediation bodies.

The 30 already on the preferred list include solicitors and barristers who mediate both full and part-time in 'mainstream' commercial disputes and have been recognised by CEDR as leading mediators.

CEDR, which last month signed up former Lord Chief Justice Lord Woolf to head a new international division, is currently in talks to bring more mediators into the scheme.

While CEDR, which covers its costs by charging a percentage of mediators' fees, will continue to refer work on an ad hoc basis to advisers who refuse to enter lock-in agreements, preference will be given to regular advisers.

CEDR chief executive Karl Mackie told Legal Week: "We recognise the market is changing and it is time to restructure and put in place a more sophisticated system.

"We are trying to educate lawyers that it is not just 'one mediator-one day' that fits all disputes. We would often recommend two mediators and would also put together mediators with different specialisations."

However, the move has received an initially mixed response from mediators, some of whom are concerned about the prospect of being pressured into tying themselves to one body.

One CEDR-registered mediator told Legal Week: "There are some good mediators around who are not getting recognised. I think exclusivity agreements with CEDR will make it harder for some people to get a share of the work."