Welsh lawyers are hoping to cash in on extra work following a ruling allowing challenges to Welsh Assembly decisions to be heard in Cardiff not London.
A practice direction issued last week by the Lord Chief Justice, Lord Bingham, creates a Crown Office in Cardiff.
The direction also advises lawyers on how to spot devolutionary matters and on how and where to deal with them.
Barrister Nicholas Cooke QC, of 9 Park Place chambers in Cardiff and co-author of the practice direction, says clients may be more interested in having lawyers in Wales who know the area and the new regulations.
He says: "The boot will be on the other foot. It was frequently necessary for Welsh lawyers to have an agent in London to sort out the paperwork and so on. Now English lawyers may need Cardiff agents."
Nic Parry, litigation partner at Mold firm Llewellyn Jones & Co and another co-author, says: "I'm delighted and excited. This is the first time for centuries that anything of this kind has been written for Wales.
"It is important that lawyers should be aware the devolution issues could be a spanner in their case."