Fidelity Institutional Wealth Services has hired Bob Oros as executive vice president of registered investment advisor (RIA) sales and relationship management, company officials announced Friday.

As chief of RIA sales, Oros will oversee 100 employees, seven regional senior vice presidents and six sales regions. He will report to Mike Durbin, president of the Fidelity RIA custody unit, which holds $502 billion in assets for more than 3,000 RIA clients.

Oros, who starts at Fidelity on Monday, takes over the slot previously held Scott Dell'Orfano, who last fall was appointed to the newly created position of managing strategic initiatives.

To join Fidelity, Oros resigned as national sales manager of Trust Co. of America, a position he held since October 2010. Prior to that, Oros held other sales positions at LPL Financial LLC and Charles Schwab & Co. Inc.