Tony Wells has "shocked" barristers at the commercial set Hardwicke Building by resigning as chief executive to become chambers director at Cherie Booth's chancery set 4-5 Gray's Inn Square.
Wells was at Hardwicke Building for five years and will start "in the next six months".
He takes over from the highly-respected senior clerk of 40 years, Leslie Page, who left last December after what is understood to be a dispute with the chambers over its decision to appoint a chambers director.
Wells will become one of the highest paid chambers directors, and says reports of a £100,000 salary are "a gross insult".
Elizabeth Appleby QC, who jointly heads 4-5 Gray's Inn Square with Michael Beloff QC, said: "We felt that we needed to appoint an experienced manager to run chambers on professional lines."
Wells said the challenge of running such a high profile set was too good to turn down. Fifteen of the set's 47 tenants are QCs, and another QC, Richard Spearman, is joining from 5 Raymond Buildings at the end of the month.
The new "top man" in the chambers is expected to sort out the clerking room where there has been "a hiatus" since Page's departure.
Romie Tager QC, of Hardwicke Building, which has 71 tenants, said: "We regard his new job as a compliment to Hardwicke Building."
Wells will take an active role in finding his replacement or replacements. Tager said the task of running the set might now be too big for one person.