Jay Mercer, executive director of Berkshire LSC, takes over at the London South council after the resignation of Vic Seddon.
Mr Mercer said he is "looking forward" to working with London South's chairman, Roy Charles. "I genuinely believe in making a new start," he said.
Mr Seddon's resignation letter to John Harwood, LSC national chief executive, accused Mr Charles of spending money without proper process and not being committed to post-16 targets. Mr Charles denies the accusations.
Auditors are investigating Mr Seddon's complaints.