Investec updated the market on its succession planning on Tuesday, reporting that group chief executive Stephen Koseff and managing director Bernard Kantor would step down from their roles on 1 October.
The FTSE 250 firm said that, from that date until 31 March 2019, they would continue to serve as executive directors and be available to provide support and advice to the incoming executives.
As from 1 April 2019, they would become non-executive directors.
Additionally, Glynn Burger, group risk and finance director, would retire on 31 March 2019, the board said.
Burger would become a non-executive director on certain subsidiary and associate boards, and remain available and willing to assist "in any capacity" that the new management team might require him for.
Investec confirmed that Fani Titi, who had been a non-executive director on the Investec Group board since January 2004 and chairman of the group since November 2011, as well as Hendrik du Toit - the founding CEO of Investec Asset Management and an executive director of the group since December 2010 - would be appointed as CEO designates on 1 April.
On 1 October they would become joint CEOs of the group, and would be held jointly accountable and responsible for the leadership and management of the Investec Group.
Du Toit would remain CEO of Investec Asset Management until 30 September 2018, to ensure an orderly transition in that business.
Kim McFarland, chief operating officer and chief financial officer of Investec Asset Management since December 1993, would take over as group finance director on 1 April 2019.
McFarland would become an executive director on that date.
She would also continue with her duties as COO and CFO of Investec Asset Management until 31 March 2019, also to support an orderly transition in that business.
The board added that Ciaran Whelan - currently global joint head of the specialist bank and global head of private banking - would be appointed to the Investec group board as an executive director on 1 April.
Whelan would succeed Glynn Burger as director of risk on 1 April 2019, and remain the global head of the private bank until 31 March 2019.
Fani Titi would step down as group chairman on 31 March, with Perry Crosthwaite - the Investec Group's senior independent non-executive director - becoming chairman of the group on 1 April.
Perry Crosthwaite was appointed as a non-executive director of the board in June 2010.
Fani Titi would also step down as chairman of Investec Bank Ltd on 1 April, with Khumo Shuenyane assuming that position.
Shuenyane has been a director of Investec Bank Ltd since August 2014.
Additionally, Fani Titi would step down as chairman of Investec Bank plc on 1 April 2018, with Brian Stevenson assuming that position.
Stevenson has been a director of Investec Bank plc since September 2016.
"When we joined Investec almost 40 years ago we aspired to develop a leading financial services group focused on our clients' needs," said CEO Stephen Koseff.
"We have worked with most of our senior management team for over 20 years and we are very proud of what we have accomplished as a team."
Koseff said the group was "well placed" to take advantage of the opportunities that lay ahead, adding that under the new executive leadership team Investec would continue to go from strength to strength.
"We are confident that the complementary skills of the new joint CEOs and their deep existing knowledge of Investec put us in an excellent position to continue the strong momentum at the group.
"We look forward to serving as non-executive directors on the board."