A new addition has helped Focus Financial Partners, the largest partnership of independent wealth management firms, further develop its New York presence.

Focus announced on Thursday the addition of the Westchester, N.Y. based investment advisor, The Portfolio Strategy Group (PSG). PSG, with over $1 billion in client assets, provides investment management for more than 200 clients around the U.S.

Focus founder and chief executive Rudy Adolf said he is excited to bring on this team and to expand the firm’s presence in the “attractive and underpenetrated” N.Y. market. “PSG’s investment management expertise will be a resource to other partners and will strengthen our ability to serve clients,” Adolf said in a statement.

PSG was founded by managing partner Richard Yoken in 1990 and serves high-net worth entrepreneurs and professionals.

In looking for a partner, Yoken said retaining his firm’s independence was a top priority. “Through our partnership with Focus, our clients are reassured that we will maintain our culture and rigorous investment management process for the long term,” Yoken said in a statement. “We also look forward to working with Focus to attract additional experienced investment professionals and benefit from the experiences of other Focus Partners.”

Silver Lane Advisors advised PSG on the transaction.