Landmark Chambers chief executive Joel Hagan is quitting the set, just two years after joining as its first non-lawyer leader.
Hagan moved to the specialist planning set from the BBC in January 2005 with the aim of helping its development.
He told The Lawyer he had not yet decided where to move on to, but said he was looking for opportunities "both inside and outside the law".
"I think that what I set out to achieve at Landmark has been substantially accomplished, and I think they're ready for the next stage too," Hagan explained.
During Hagan's tenure Landmark has increased in size to more than 60 tenants turning over £16m and has consolidated the 2003 merger between Eldon Chambers and 4 Breams Buildings, which created the set.
Earlier this year Christopher Katkowski QC took over as head of chambers.