Brooks will be succeeded by Kevin Parry following a period of transition and Philip Mallinckrodt is to join the board from January 1.
Parry has been a non-executive director at the firm since 2003, chairman of the audit committee and member of the remuneration committee. He becomes an executive director of the company in his new role and will join the group management committee.
Schroders chief executive Michael Dobson says: “Stephen leaves us after having made an important contribution over the past three years. He goes with our thanks and best wishes. I look forward to working closely with Kevin whose role as chairman of the audit committee for the past five years positions him well for his new role as chief financial officer.”