Douglas B. Sieg was named managing partner of Lord, Abbett & Co., spokesman Jon Brubaker said.
Effective April 1, he replaces Daria L. Foster, who announced her intention to retire on March 31.
As managing partner, Mr. Sieg will lead the company and oversee the firm's strategic direction.
Mr. Sieg was partner, client services at Lord Abbett. It has not yet been determined who will be assuming Mr. Sieg's role, said Mr. Brubaker.
Lord Abbett has $160.4 billion in assets under management.