Tullow Oil plc has appointed non-executive director (NED) Martin Greenslade as senior independent NED.
He replaces Jeremy Wilson who will retire at the end of November.
Mr Greenslade will also be a member of the nominations and remuneration committees.
The company has also appointed NED Genevieve Sangudi as a member of the audit committee.
Tullow added it was conducting its annual board evaluation, which includes the size and composition of the board and its committees.