Tiger 21's Magnolia Purchasing Advisors helps members and other clients buy and charter jets.

Tiger 21, the peer-to-peer network for ultrawealthy investors, has experienced substantial growth in this decade, and is now looking to move to the next level.

The organization announced Monday that it had formed Tiger 21 Holdings, which will house both its membership operations and its purchasing advisor services unit, and had brought on board marketing and management executive Barbara Goodstein to serve as president and chief executive of the parent company.

Founded in 1999 as an idea-sharing forum for New York-based entrepreneurs who had recently sold their business, Tiger 21 has grown to 325 members groups in 18 North American cities with combined personal investable assets of more than $30 billion.

Tiger 21 formed Magnolia Purchasing Advisors in 2012 to leverage the combined purchasing power of its high-net-worth members when buying big-ticket products and services.

The unit, which is about to complete its thousandth transaction, offers an umbrella liability insurance group policy with upward of $3 billion of coverage in place; aviation charter and purchase; and artwork, automobiles and other collectibles.

In the past year, Magnolia has begun serving clients beyond Tiger 21’s membership base, according to a statement.

The announcement said Goodstein’s task would be to further build the membership and the advisory divisions to serve both members and nonmembers.

“Tiger 21’s recent growth has allowed us to expand our sights, and I am excited to have Barbara partner with me to focus on and seize the opportunities that our success has created,” Michael Sonnenfeldt, the organization’s founder and chairman, said in the statement.

“Barbara has implemented highly successful development strategies in her other senior leadership roles, and we are certain that she will be able to do the same for us.”

According to the statement, Goodstein has built businesses for American Express, Instinet.com and JPMorgan Chase. She served as chief marketing officer for AXA Equitable, and most recently for Vonage Holdings Corp. She also sits on the board of investment management company Manning and Napier.

Jonathan Kempner will continue to serve as president of Tiger 21, and Clay Speakman as president of Magnolia Purchasing Advisors.

— Check out Where the Ultra-Wealthy Invest Money: Tiger 21 on ThinkAdvisor.