Sanjeev Shah is leaving the fund management industry after 17 years at Fidelity Worldwide Investment.
Mr Shah has been managing the Fidelity Special Situations fund for five years and this will be taken over by Alex Wright.
The two managers will work closely together over the next few months before Mr Wright takes over on 1 January 2014.
Mr Shah, who joined Fidelity in 1996 and has managed the Fidelity Special Situations since 2008, will take up a new role at Fidelity's PM Academy which develops new investment talent.
Mr Wright will remain manager of the Fidelity Special Values Plc and co-manager of Fidelity UK Smaller Companies fund with Jonathan Winton.
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He follows the same contrarian/value approach as Mr Shah and invests in unloved stocks with limited downside risk and potential for positive change.
Dominic Rossi, global chief investment officer of equities at Fidelity, said: "We would like to take this opportunity to thank Sanjeev for the tremendous contribution he has made to the firm and our clients' portfolios over the last 17 years. He has delivered strong performance to investors in what has been an extremely challenging period for markets.
"Alex has a strong track record in both small cap and all cap disciplines and we are confident that he will deliver strong performance for investors in the Fidelity Special Situations Fund."

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