Douglas B. Sieg has been appointed managing partner for Lord Abbett & Co. LLC, an independent, privately held investment firm based in Jersey City, N.J., replacing Daria L. Foster, who is retiring.

In his new role effective April 1, Sieg will lead the organization.

Foster, the first woman to hold the position, has led the firm for the past 11 years and was the ninth managing partner. Lord Abbett currently has more than $160.4 billion in assets under management.

Sieg most recently held the title of partner, client services, and was responsible for overseeing the U.S. Retail, U.S. Institutional, and International markets, as well as the product strategy, marketing and corporate communications teams.